Compounds, compositions and methods of agelastatin alkaloids

ABSTRACT

The present invention, among other things, provides compounds, compositions and methods for treatment of cancer. In some embodiments, the present invention provides methods for treating blood cancer using agelastatin alkaloids.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/255,224, filed on Sep. 2, 2016, which is a continuation of U.S.patent application Ser. No. 14/490,146, filed on Sep. 18, 2014, whichclaims the benefit of U.S. Provisional Application No. 61/880,018, filedon Sep. 19, 2013, the contents of each aforementioned application areincorporated by reference in their entireties.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with government support under Grant No. GM074825awarded by the National Institutes of Health. The government has certainrights in the invention.

FIELD OF THE INVENTION

The present invention generally relates to, among other things,compounds, compositions and methods for treating cancer.

SUMMARY

Among other things, the present invention provides compounds,compositions and methods for treating a blood cancer. In someembodiments, the present invention provides a method for treating ablood cancer. In some embodiments, the present invention provides amethod for treating a blood cancer in a subject in need thereof,comprising administering to the subject a therapeutically effectiveamount of an agelastatin alkaloid.

In some embodiments, the present invention provides a pharmaceuticalcomposition of a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra. In some embodiments, aprovided composition is for treating blood cancers.

In some embodiments, the present invention provides a method fortreating a blood cancer in a subject in need thereof, comprisingadministering to the subject a therapeutically effective amount of acompound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra.

In some embodiments, the present invention provides a method forinhibiting growth of blood cancer cells. In some embodiments, thepresent invention provides a method for inhibiting growth of bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra.

In some embodiments, the present invention provides a method forinhibiting proliferation of blood cancer cells. In some embodiments, thepresent invention provides a method for inhibiting proliferation ofblood cancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra.

In some embodiments, the present invention provides a method forpromoting apoptosis of blood cancer cells. In some embodiments, thepresent invention provides a method for promoting apoptosis of bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra.

In some embodiments, the present invention provides a method forarresting cell cycle in blood cancer cells. In some embodiments, thepresent invention provides a method for arresting cell cycle in bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra.

In some embodiments, the present invention provides a method forinducing arrest in G2/M phase in blood cancer cells. In someembodiments, the present invention provides a method for inducing arrestin G2/M phase in blood cancer cells, comprising administering a compoundof formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently described in detail, infra.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1. Hemolytic activity of (−)-agelastatins A-F and advancedintermediates. Compounds were tested at 333 μM and hemolysis wasevaluated after 2 h. DMSO and water served as the negative and positivecontrols for hemolysis, respectively. Error bars represent standarddeviation of the mean, n=3.

FIG. 2. (−)-Agelastatins A (1) and D (4) both induce caspase-dependentapoptotic cell death. Western blot analysis of procaspase-3 and PARP-1cleavage at 24 hours in U-937 cells using β-actin as loading control.Compounds were tested at indicated concentrations and STS (10 nM);C3=caspase-3; PARP=poly(ADP-ribose) polymerase 1; PC3=procaspase-3;STS=staurosporine.

FIG. 3. (−)-Agelastatins A (1) and D (4) both induced dose-dependentapoptosis. Analysis of phosphatidylserine exposure and propidium iodideinclusion at 21 hours in U-937 cells. Compounds were tested at indicatedconcentrations and STS was used as a positive control for apoptosis.Samples were analyzed by flow cytometry for the relative timing ofphosphatidylserine exposure relative to PI inclusion. FITC=fluoresceinisothiocyanate; PI=propidium iodide; STS=staurosporine.

FIG. 4. (−)-Agelastatins A (1) and D (4) both exhibit dose-dependentG2/M cell cycle arrest in synchronized U-937 cells after 16 hours.Samples were fixed, treated with an RNAse, stained with PI, and analyzedby flow cytometry. Taxol, a microtubule stabilizer, was used as apositive control. Error bars represent standard deviation of the mean,n=3. *p<0.01. PI=propidium iodide.

FIG. 5. Minimized energy conformations of imides S17 and S18 (Spartan06, Density Functional, B3LYP, 6·31G* was used for the calculation).

FIG. 6. Minimized energy conformations of acyliminium ion S19 and 8(Spartan 06, Density Functional, B3LYP, 6·31G* was used for thecalculation).

FIG. 7. Linear approximation of ln[SM] vs time of(+)-O-methyl-pre-agelastatins A (39) and D (53).

FIG. 8. Agelastatin A (1) and agelastatin D (4) do not affect tubulindynamics. HeLa cells were treated with compound for 16 hours, fixed,stained, and visualized using confocal microscopy. Colchicine (colch)and taxol were used as positive controls for tubulin destabilization andstabilization, respectively.

FIG. 9. Crystal Structure of 13-desbromo-methylester S25.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS 1. General Description ofCertain Embodiments of the Invention

Among other things, the present invention provides compounds,compositions and methods for treating blood cancers.

In some embodiments, the present invention provides agelastatincompounds. In some embodiments, the present invention provides acomposition comprising an agelastatin compound. In some embodiments, anagelastatin compound in a provided composition has the structure offormula I. In some embodiments, the present invention provides apharmaceutical composition of a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention provides a composition fortreating a blood cancer in a subject in need thereof, comprising acompound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention recognizes that agelastatinalkaloids, e.g., a compound of formula I, are particularly effective anduseful for treating blood cancer. In some embodiments, the presentinvention provides methods for treating a blood cancer in a subject inneed thereof, comprising administering to the subject a therapeuticallyeffective amount of an agelastatin alkaloid, or a pharmaceuticallyacceptable salt thereof. In some embodiments, the present inventionprovides methods for inhibiting growth of blood cancer cells, comprisingadministering an agelastatin alkaloid, or a pharmaceutically acceptablesalt thereof. In some embodiments, the present invention providesmethods for inhibiting proliferation of blood cancer cells, comprisingadministering an agelastatin alkaloid, or a pharmaceutically acceptablesalt thereof. In some embodiments, the present invention providesmethods for promoting apoptosis of blood cancer cells, comprisingadministering an agelastatin alkaloid, or a pharmaceutically acceptablesalt thereof. In some embodiments, the present invention providesmethods for arresting cell cycle in blood cancer cells, comprisingadministering an agelastatin alkaloid, or a pharmaceutically acceptablesalt thereof. In some embodiments, the present invention providesmethods for arresting G2/M phase in blood cancer cells, comprisingadministering an agelastatin alkaloid, or a pharmaceutically acceptablesalt thereof. In some embodiments, an agelastatin alkaloid in providedmethod has the structure of formula I.

In some embodiments, the present invention provides a method fortreating a blood cancer in a subject in need thereof, comprisingadministering to the subject a therapeutically effective amount of acompound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention provides a method forinhibiting growth of blood cancer cells. In some embodiments, thepresent invention provides a method for inhibiting growth of bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention provides a method forinhibiting proliferation of blood cancer cells. In some embodiments, thepresent invention provides a method for inhibiting proliferation ofblood cancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention provides a method forpromoting apoptosis of blood cancer cells. In some embodiments, thepresent invention provides a method for promoting apoptosis of bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention provides a method forarresting cell cycle in blood cancer cells. In some embodiments, thepresent invention provides a method for arresting cell cycle in bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

In some embodiments, the present invention provides a method forinducing arrest in G2/M phase in blood cancer cells. In someembodiments, the present invention provides a method for inducing arrestin G2/M phase in blood cancer cells, comprising administering a compoundof formula I:

or a pharmaceutically acceptable salt thereof, wherein:

-   -   R¹ is —H or —CH₃;    -   R² is —OH or —OCH₃;    -   R³ is —H or —OH; and    -   R⁴ is —H, or —Br when R¹ is —CH₃.

2. Definitions

Compounds of the present invention include those described generallyherein, and are further illustrated by the classes, subclasses, andspecies disclosed herein. As used herein, the following definitionsshall apply unless otherwise indicated. For purposes of this invention,the chemical elements are identified in accordance with the PeriodicTable of the Elements, CAS version, Handbook of Chemistry and Physics,93^(rd) Ed. Additionally, general principles of organic chemistry aredescribed in “Organic Chemistry”, 2^(nd) Ed, Thomas N. Sorrell,University Science Books, Sausalito: 2005, and “March's Advanced OrganicChemistry”, 6^(th) Ed., Smith, M. B. and March, J., John Wiley & Sons,New York: 2007, the entire contents of which are hereby incorporated byreference.

The term “aliphatic” or “aliphatic group”, as used herein, means astraight-chain (i.e., unbranched) or branched, substituted orunsubstituted hydrocarbon chain that is completely saturated or thatcontains one or more units of unsaturation, or a monocyclic hydrocarbon,bicyclic hydrocarbon, or polycyclic hydrocarbon that is completelysaturated or that contains one or more units of unsaturation, but whichis not aromatic (also referred to herein as “carbocycle,”“cycloaliphatic” or “cycloalkyl”), that has, unless otherwise specified,a single point of attachment to the rest of the molecule. Unlessotherwise specified, aliphatic groups contain 1-30 aliphatic carbonatoms. In some embodiments, aliphatic groups contain 1-20 aliphaticcarbon atoms. In other embodiments, aliphatic groups contain 1-10aliphatic carbon atoms. In still other embodiments, aliphatic groupscontain 1-5 aliphatic carbon atoms, and in yet other embodiments,aliphatic groups contain 1, 2, 3, or 4 aliphatic carbon atoms. Suitablealiphatic groups include, but are not limited to, linear or branched,substituted or unsubstituted alkyl, alkenyl, alkynyl groups and hybridsthereof such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl or(cycloalkyl)alkenyl.

The term “cycloaliphatic,” as used herein, refers to saturated orpartially unsaturated cyclic aliphatic monocyclic, bicyclic, orpolycyclic ring systems, as described herein, having from 3 to 14members, wherein the aliphatic ring system is optionally substituted asdefined above and described herein. Cycloaliphatic groups include,without limitation, cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl,cyclohexyl, cyclohexenyl, cycloheptyl, cycloheptenyl, cyclooctyl,cyclooctenyl, norbornyl, adamantyl, and cyclooctadienyl. In someembodiments, the cycloalkyl has 3-6 carbons. The terms “cycloaliphatic,”may also include aliphatic rings that are fused to one or more aromaticor nonaromatic rings, such as decahydronaphthyl or tetrahydronaphthyl,where the radical or point of attachment is on the aliphatic ring. Insome embodiments, a carbocyclic group is bicyclic. In some embodiments,a carbocyclic group is tricyclic. In some embodiments, a carbocyclicgroup is polycyclic. In some embodiments, “cycloaliphatic” (or“carbocycle” or “cycloalkyl”) refers to a monocyclic C₃-C₆ hydrocarbon,or a C₈-C₁₀ bicyclic hydrocarbon that is completely saturated or thatcontains one or more units of unsaturation, but which is not aromatic,that has a single point of attachment to the rest of the molecule, or aC₉-C₁₆ tricyclic hydrocarbon that is completely saturated or thatcontains one or more units of unsaturation, but which is not aromatic,that has a single point of attachment to the rest of the molecule.

As used herein, the term “alkyl” is given its ordinary meaning in theart and may include saturated aliphatic groups, including straight-chainalkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic)groups, alkyl substituted cycloalkyl groups, and cycloalkyl substitutedalkyl groups. In certain embodiments, a straight chain or branched chainalkyl has about 1-20 carbon atoms in its backbone (e.g., C₁-C₂₀ forstraight chain, C₂-C₂₀ for branched chain), and alternatively, about1-10. In some embodiments, a cycloalkyl ring has from about 3-10 carbonatoms in their ring structure where such rings are monocyclic, bicyclicor polycyclic, and alternatively about 5, 6 or 7 carbons in the ringstructure. In some embodiments, an alkyl group may be a lower alkylgroup, wherein a lower alkyl group comprises 1-4 carbon atoms (e.g.,C₁-C₄ for straight chain lower alkyls).

As used herein, the term “alkenyl” refers to an alkyl group, as definedherein, having one or more double bonds.

As used herein, the term “alkynyl” refers to an alkyl group, as definedherein, having one or more triple bonds.

The term “heteroalkyl” is given its ordinary meaning in the art andrefers to alkyl groups as described herein in which at least one carbonatom, optionally with one or more attached hydrogen atoms, is replacedwith a heteroatom (e.g., oxygen, nitrogen, sulfur, phosphorus, selenium,boron and the like). Examples of heteroalkyl groups include, but are notlimited to, alkoxy, poly(ethylene glycol)-, alkyl-substituted amino,tetrahydrofuranyl, piperidinyl, morpholinyl, etc. In some embodiments, aheteroatom may be oxidized (e.g., —S(O)—, —S(O)₂—, —N(O)—, —P(O)— andthe like).

The term “aryl” used alone or as part of a larger moiety as in“aralkyl,” “aralkoxy,” or “aryloxyalkyl,” refers to monocyclic, bicyclicor polycyclic ring systems having a total of five to fourteen ringmembers, wherein at least one ring in the system is aromatic and whereineach ring in the system contains 3 to 7 ring members. The term “aryl”may be used interchangeably with the term “aryl ring.” In certainembodiments of the present invention, “aryl” refers to an aromatic ringsystem which includes, but not limited to, phenyl, biphenyl, naphthyl,binaphthyl, anthracyl and the like, which may bear one or moresubstituents. Also included within the scope of the term “aryl,” as itis used herein, is a group in which an aromatic ring is fused to one ormore non-aromatic rings, such as indanyl, phthalimidyl, naphthimidyl,phenanthridinyl, or tetrahydronaphthyl, and the like.

The terms “heteroaryl” and “heteroar-,” used alone or as part of alarger moiety, e.g., “heteroaralkyl,” or “heteroaralkoxy,” refer togroups having 5 to 10 ring atoms (i.e., monocyclic or bicyclic), in someembodiments 5, 6, 9, or 10 ring atoms. In some embodiments, such ringshave 6, 10, or 14 π electrons shared in a cyclic array; and having, inaddition to carbon atoms, from one to five heteroatoms. The term“heteroatom” refers to nitrogen, oxygen, or sulfur, and includes anyoxidized form of nitrogen or sulfur, and any quaternized form of a basicnitrogen. Heteroaryl groups include, without limitation, thienyl,furanyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl,oxazolyl, isoxazolyl, oxadiazolyl, thiazolyl, isothiazolyl,thiadiazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, indolizinyl,purinyl, naphthyridinyl, and pteridinyl. In some embodiments, aheteroaryl is a heterobiaryl group, such as bipyridyl and the like. Theterms “heteroaryl” and “heteroar-”, as used herein, also include groupsin which a heteroaromatic ring is fused to one or more aryl,cycloaliphatic, or heterocyclyl rings, where the radical or point ofattachment is on the heteroaromatic ring. Non-limiting examples includeindolyl, isoindolyl, benzothienyl, benzofuranyl, dibenzofuranyl,indazolyl, benzimidazolyl, benzthiazolyl, quinolyl, isoquinolyl,cinnolinyl, phthalazinyl, quinazolinyl, quinoxalinyl, 4H-quinolizinyl,carbazolyl, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl,tetrahydroquinolinyl, tetrahydroisoquinolinyl, andpyrido[2,3-b]-1,4-oxazin-3(4H)-one. A heteroaryl group may be mono- orbicyclic. The term “heteroaryl” may be used interchangeably with theterms “heteroaryl ring,” “heteroaryl group,” or “heteroaromatic,” any ofwhich terms include rings that are optionally substituted. The term“heteroaralkyl” refers to an alkyl group substituted by a heteroaryl,wherein the alkyl and heteroaryl portions independently are optionallysubstituted.

As used herein, the terms “heterocycle,” “heterocyclyl,” “heterocyclicradical,” and “heterocyclic ring” are used interchangeably and refer toa stable 5- to 7-membered monocyclic or 7-10-membered bicyclicheterocyclic moiety that is either saturated or partially unsaturated,and having, in addition to carbon atoms, one or more, preferably one tofour, heteroatoms, as defined above. When used in reference to a ringatom of a heterocycle, the term “nitrogen” includes a substitutednitrogen. As an example, in a saturated or partially unsaturated ringhaving 0-3 heteroatoms selected from oxygen, sulfur or nitrogen, thenitrogen may be N (as in 3,4-dihydro-2H-pyrrolyl), NH (as inpyrrolidinyl), or ⁺NR (as in N-substituted pyrrolidinyl).

A heterocyclic ring can be attached to its pendant group at anyheteroatom or carbon atom that results in a stable structure and any ofthe ring atoms can be optionally substituted. Examples of such saturatedor partially unsaturated heterocyclic radicals include, withoutlimitation, tetrahydrofuranyl, tetrahydrothienyl pyrrolidinyl,piperidinyl, pyrrolinyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl,decahydroquinolinyl, oxazolidinyl, piperazinyl, dioxanyl, dioxolanyl,diazepinyl, oxazepinyl, thiazepinyl, morpholinyl, and quinuclidinyl. Theterms “heterocycle,” “heterocyclyl,” “heterocyclyl ring,” “heterocyclicgroup,” “heterocyclic moiety,” and “heterocyclic radical,” are usedinterchangeably herein, and also include groups in which a heterocyclylring is fused to one or more aryl, heteroaryl, or cycloaliphatic rings,such as indolinyl, 3H-indolyl, chromanyl, phenanthridinyl, ortetrahydroquinolinyl. A heterocyclyl group may be mono- or bicyclic. Theterm “heterocyclylalkyl” refers to an alkyl group substituted by aheterocyclyl, wherein the alkyl and heterocyclyl portions independentlyare optionally substituted.

As used herein, the term “partially unsaturated” refers to a ring moietythat includes at least one double or triple bond. The term “partiallyunsaturated” is intended to encompass rings having multiple sites ofunsaturation, but is not intended to include aryl or heteroarylmoieties, as herein defined.

The term “heteroatom” means one or more of boron, oxygen, sulfur,selenium, nitrogen, phosphorus, or silicon (including, any oxidized formof nitrogen, sulfur, selenium, phosphorus, or silicon; the quaternizedform of any basic nitrogen; or a substitutable nitrogen of aheterocyclic ring, for example N (as in 3,4-dihydro-2H-pyrrolyl), NH (asin pyrrolidinyl) or NR⁺ (as in N-substituted pyrrolidinyl)).

The term “unsaturated,” as used herein, means that a moiety has one ormore units of unsaturation.

The term “halogen” means F, Cl, Br, or I.

As described herein, compounds of the invention may contain “optionallysubstituted” moieties. In general, the term “substituted,” whetherpreceded by the term “optionally” or not, means that one or morehydrogen atoms of the designated moiety are replaced with a suitablesubstituent. Unless otherwise indicated, an “optionally substituted”group may have a suitable substituent at each substitutable position ofthe group, and when more than one position in any given structure may besubstituted with more than one substituent selected from a specifiedgroup, the substituent may be either the same or different at everyposition. Combinations of substituents envisioned by this invention arepreferably those that result in the formation of stable or chemicallyfeasible compounds. The term “stable,” as used herein, refers tocompounds that are not substantially altered when subjected toconditions to allow for their production, detection, and, in certainembodiments, their recovery, purification, and use for one or more ofthe purposes disclosed herein.

Suitable monovalent substituents on a substitutable carbon atom of an“optionally substituted” group are independently halogen;—(CH₂)₀₋₄R^(∘); —(CH₂)₀₋₄OR^(∘); —(CH₂)₀₋₄SR^(∘); —(CH₂)₀₋₄S(O)R^(∘);—O(CH₂)₀₋₄R^(∘), —O—(CH₂)₀₋₄C(O)OR^(∘); —(CH₂)₀₋₄CH(OR^(∘))₂;—(CH₂)₀₋₄Ph, which may be substituted with R^(∘); —(CH₂)₀₋₄O(CH₂)₀₋₁Phwhich may be substituted with R⁶⁰² ; —CH═CHPh, which may be substitutedwith R^(∘); —(CH₂)₀₋₄O(CH₂)₀₋₁-pyridyl which may be substituted withR^(∘); —NO₂; —CN; —N₃; —(CH₂)₀₋₄N(R^(∘))₂; —(CH₂)₀₋₄N(R^(∘))C(O)R^(∘);—N(R^(∘))C(S)R^(∘); —(CH₂)₀₋₄N(R^(∘))C(O)NR^(∘) ₂; —N(R^(∘))C(S)NR^(∘)₂; —(CH₂)₀₋₄N(R^(∘))C(O)OR^(∘); —N(R^(∘))N(R^(∘))C(O)R^(∘);—N(R^(∘))N(R^(∘))C(O)NR^(∘) ₂; —N(R^(∘))N(R^(∘))C(O)OR^(∘);—(CH₂)₀₋₄C(O)R^(∘); —C(S)R^(∘); —(CH₂)₀₋₄C(O)OR^(∘);—(CH₂)₀₋₄C(O)SR^(∘); —(CH₂)₀₋₄C(O)OSiR^(∘) ₃; —(CH₂)₀₋₄OC(O)R^(∘);—OC(O)(CH₂)₀₋₄SR; —SC(S)SR^(∘); —(CH₂)₀₋₄SC(O)R^(∘); —(CH₂)₀₋₄C(O)NR^(∘)₂; —C(S)NR^(∘) ₂; —C(S)SR^(∘); —SC(S)SR^(∘); —(CH₂)₀₋₄OC(O)NR^(∘) ₂;—C(O)N(OR^(∘))R^(∘); —C(O)C(O)R^(∘); —C(O)CH₂C(O)R^(∘);—C(NOR^(∘))R^(∘); —(CH₂)₀₋₄SSR^(∘); —(CH₂)₀₋₄S(O)₂R^(∘);—(CH₂)₀₋₄S(O)₂OR^(∘); —(CH₂)₀₋₄OS(O)₂R^(∘); —S(O)₂NR^(∘) ₂;—(CH₂)₀₋₄S(O)R^(∘); —N(R^(∘))S(O)₂NR^(∘) ₂; —N(R^(∘))S(O)₂R^(∘);—N(OR^(∘))R^(∘); —C(NH)NR^(∘) ₂; —P(O)₂R^(∘); —P(O)R^(∘) ₂;—P(O)(OR^(∘))R^(∘); —P(O)(OR^(∘) ₂; —OP(O)R^(∘) ₂; —OP(O)(OR^(∘))R^(∘);—OP(O)(OR^(∘))₂; —PR^(∘) ₂; —P(OR^(∘))R^(∘); —P(OR^(∘))₂; —OPR^(∘) ₂;—OP(OR^(∘))R^(∘); —OP(OR^(∘))₂; —SiR^(∘) ₃; —OSiR^(∘) ₃; —SeR^(∘);—(CH₂)₀₋₄SeSeR^(∘); —B(R^(∘))₂, —B(OR^(∘))₂, —(C₁₋₄ straight orbranched)alkylene)O—N(R^(∘))₂; or —(C₁₋₄ straight or branchedalkylene)C(O)O—N(R^(∘))₂; wherein each R^(∘) may be substituted asdefined below and is independently hydrogen, C₁₋₆ aliphatic, —CH₂Ph,—O(CH₂)₀₋₁Ph, —CH₂-(5-6 membered heteroaryl ring), or a 5-6-memberedsaturated, partially unsaturated, or aryl ring having 0-4 heteroatomsindependently selected from nitrogen, oxygen, or sulfur, or,notwithstanding the definition above, two independent occurrences ofR^(∘), taken together with their intervening atom(s), form a3-12-membered saturated, partially unsaturated, or aryl mono- orbicyclic ring having 0-6 heteroatoms independently selected fromnitrogen, oxygen, or sulfur, which may be substituted as defined below.

Suitable monovalent substituents on R^(∘) (or the ring formed by takingtwo independent occurrences of R^(∘) together with their interveningatoms), are independently halogen, —(CH₂)₀₋₂R^(●), -(haloR^(●)),—(CH₂)₀₋₂OH, —(CH₂)₀₋₂OR^(●), —(CH₂)₀₋₂CH(OR^(●))₂; —O(haloR^(●)), —CN,—N₃, —(CH₂)₀₋₂C(O)R^(●), —(CH₂)₀₋₂C(O)OH, —(CH₂)₀₋₂C(O)OR^(●),—(CH₂)₀₋₂SR^(●), —(CH₂)₀₋₂SH, —(CH₂)₀₋₂NH₂, —(CH₂)₀₋₂NHR^(●),—(CH₂)₀₋₂NR^(●) ₂, —NO₂, —SiR^(●) ₃, —OSiR^(●) ₃, —C(O)SR^(●), —(C₁₋₄straight or branched alkylene)C(O)OR^(●), or —SSR^(●) wherein each R^(●)is unsubstituted or where preceded by “halo” is substituted only withone or more halogens, and is independently selected from C₁₋₄ aliphatic,—CH₂Ph, —O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partiallyunsaturated, or aryl ring having 0-4 heteroatoms independently selectedfrom nitrogen, oxygen, or sulfur. Suitable divalent substituents on asaturated carbon atom of R^(∘) include ═O and ═S.

Suitable divalent substituents on a suitable carbon atom of an“optionally substituted” group include the following: ═O, ═S, ═NNR*₂,═NNHC(O)R*, ═NNHC(O)OR*, ═NNHS(O)₂R*, ═NR*, ═NOR*, —O(C(R*₂))₂₋₃O—, or—S(C(R*₂))₂₋₃S—, wherein each independent occurrence of R* is selectedfrom hydrogen, C₁₋₆ aliphatic which may be substituted as defined below,or an unsubstituted 5-6-membered saturated, partially unsaturated, oraryl ring having 0-4 heteroatoms independently selected from nitrogen,oxygen, or sulfur. Suitable divalent substituents that are bound tovicinal substitutable carbons of an “optionally substituted” groupinclude: —O(CR*₂)₂₋₃O—, wherein each independent occurrence of R* isselected from hydrogen, C₁₋₆ aliphatic which may be substituted asdefined below, or an unsubstituted 5-6-membered saturated, partiallyunsaturated, or aryl ring having 0-4 heteroatoms independently selectedfrom nitrogen, oxygen, or sulfur.

Suitable substituents on the aliphatic group of R* include halogen,—R^(●), —(haloR^(●)), —OH, —OR^(●), —O(haloR^(●)), —CN, —C(O)OH,—C(O)OR^(●), —NH₂, —NHR^(●), —NR^(●) ₂, or —NO₂, wherein each R^(●) isunsubstituted or where preceded by “halo” is substituted only with oneor more halogens, and is independently C₁₋₄ aliphatic, —CH₂Ph,—O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partially unsaturated, oraryl ring having 0-4 heteroatoms independently selected from nitrogen,oxygen, or sulfur.

Suitable substituents on a substitutable nitrogen of an “optionallysubstituted” group include —R^(†), —NR^(†) ₂, —C(O)R^(†), —C(O)OR^(†),—C(O)C(O)R^(†), —C(O)CH₂C(O)R^(†), —S(O)₂R^(†), —S(O)₂NR^(†) ₂,—C(S)NR^(†) ₂, —C(NH)NR^(†) ₂, or —N(R^(†))S(O)₂R^(†); wherein eachR^(†) is independently hydrogen, C₁₋₆ aliphatic which may be substitutedas defined below, unsubstituted —OPh, or an unsubstituted 5-6-memberedsaturated, partially unsaturated, or aryl ring having 0-4 heteroatomsindependently selected from nitrogen, oxygen, or sulfur, or,notwithstanding the definition above, two independent occurrences ofR^(†), taken together with their intervening atom(s) form anunsubstituted 3-12-membered saturated, partially unsaturated, or arylmono- or bicyclic ring having 0-4 heteroatoms independently selectedfrom nitrogen, oxygen, or sulfur.

Suitable substituents on the aliphatic group of Rt are independentlyhalogen, —R^(●), -(haloR^(●)), —OH, —OR^(●), —O(haloR^(●)), —CN,—C(O)OH, —C(O)OR^(●), —NH₂, —NHR^(●), —NR^(●) ₂, or —NO₂, wherein eachR^(●) is unsubstituted or where preceded by “halo” is substituted onlywith one or more halogens, and is independently C₁₋₄ aliphatic, —CH₂Ph,—O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partially unsaturated, oraryl ring having 0-4 heteroatoms independently selected from nitrogen,oxygen, or sulfur.

The term “chiral” is given its ordinary meaning in the art and refers toa molecule that is not superimposable with its mirror image, wherein theresulting non-superimposable mirror images are known as “enantiomers”and are labeled as either an (R) enantiomer or an (S) enantiomer.Typically, chiral molecules lack a plane of symmetry.

The term “achiral” is given its ordinary meaning in the art and refersto a molecule that is superimposable with its mirror image. Typically,achiral molecules possess a plane of symmetry.

The phrase “protecting group,” as used herein, refers to temporarysubstituents which protect a potentially reactive functional group fromundesired chemical transformations. Examples of such protecting groupsinclude esters of carboxylic acids, silyl ethers of alcohols, andacetals and ketals of aldehydes and ketones, respectively. A “Siprotecting group” is a protecting group comprising a Si atom, such asSi-trialkyl (e.g., trimethylsilyl, tributylsilyl, t-butyldimethylsilyl),Si-triaryl, Si-alkyl-diphenyl (e.g., t-butyldiphenylsilyl), orSi-aryl-dialkyl (e.g., Si-phenyldialkyl). Generally, a Si protectinggroup is attached to an oxygen atom. The field of protecting groupchemistry has been reviewed (Greene, T. W.; Wuts, P. G. M. ProtectiveGroups in Organic Synthesis, 2nd ed.; Wiley: New York, 1991). Suchprotecting groups (and associated protected moieties) are described indetail below.

Protected hydroxyl groups are well known in the art and include thosedescribed in detail in Protecting Groups in Organic Synthesis, T. W.Greene and P. G. M. Wuts, 3^(rd) edition, John Wiley & Sons, 1999, theentirety of which is incorporated herein by reference. Examples ofsuitably protected hydroxyl groups further include, but are not limitedto, esters, carbonates, sulfonates allyl ethers, ethers, silyl ethers,alkyl ethers, arylalkyl ethers, and alkoxyalkyl ethers. Examples ofsuitable esters include formates, acetates, proprionates, pentanoates,crotonates, and benzoates. Specific examples of suitable esters includeformate, benzoyl formate, chloroacetate, trifluoroacetate,methoxyacetate, triphenylmethoxyacetate, p-chlorophenoxyacetate,3-phenylpropionate, 4-oxopentanoate, 4,4-(ethylenedithio)pentanoate,pivaloate (trimethylacetate), crotonate, 4-methoxy-crotonate, benzoate,p-benylbenzoate, 2,4,6-trimethylbenzoate. Examples of suitablecarbonates include 9-fluorenylmethyl, ethyl, 2,2,2-trichloroethyl,2-(trimethylsilyl)ethyl, 2-(phenylsulfonyl)ethyl, vinyl, allyl, andp-nitrobenzyl carbonate. Examples of suitable silyl ethers includetrimethylsilyl, triethylsilyl, t-butyldimethylsilyl,t-butyldiphenylsilyl, triisopropylsilyl ether, and other trialkylsilylethers. Examples of suitable alkyl ethers include methyl, benzyl,p-methoxybenzyl, 3,4-dimethoxybenzyl, trityl, t-butyl, and allyl ether,or derivatives thereof. Alkoxyalkyl ethers include acetals such asmethoxymethyl, methylthiomethyl, (2-methoxyethoxy)methyl,benzyloxymethyl, beta-(trimethylsilyl)ethoxymethyl, andtetrahydropyran-2-yl ether. Examples of suitable arylalkyl ethersinclude benzyl, p-methoxybenzyl (MPM), 3,4-dimethoxybenzyl,O-nitrobenzyl, p-nitrobenzyl, p-halobenzyl, 2,6-dichlorobenzyl,p-cyanobenzyl, 2- and 4-picolyl ethers.

Protected amines are well known in the art and include those describedin detail in Greene (1999). Suitable mono-protected amines furtherinclude, but are not limited to, aralkylamines, carbamates, allylamines, amides, and the like. Examples of suitable mono-protected aminomoieties include t-butyloxycarbonylamino (—NHBOC),ethyloxycarbonylamino, methyloxycarbonylamino,trichloroethyloxycarbonylamino, allyloxycarbonylamino (—NHAlloc),benzyloxycarbonylamino (—NHCBZ), allylamino, benzylamino (—NHBn),fluorenylmethylcarbonyl (—NHFmoc), formamido, acetamido,chloroacetamido, dichloroacetamido, trichloroacetamido, phenylacetamido,trifluoroacetamido, benzamido, t-butyldiphenylsilyl, and the like.Suitable di-protected amines include amines that are substituted withtwo substituents independently selected from those described above asmono-protected amines, and further include cyclic imides, such asphthalimide, maleimide, succinimide, and the like. Suitable di-protectedamines also include pyrroles and the like,2,2,5,5-tetramethyl-[1,2,5]azadisilolidine and the like, and azide.

Protected aldehydes are well known in the art and include thosedescribed in detail in Greene (1999). Suitable protected aldehydesfurther include, but are not limited to, acyclic acetals, cyclicacetals, hydrazones, imines, and the like. Examples of such groupsinclude dimethyl acetal, diethyl acetal, diisopropyl acetal, dibenzylacetal, bis(2-nitrobenzyl) acetal, 1,3-dioxanes, 1,3-dioxolanes,semicarbazones, and derivatives thereof.

Protected carboxylic acids are well known in the art and include thosedescribed in detail in Greene (1999). Suitable protected carboxylicacids further include, but are not limited to, optionally substitutedC₁₋₆ aliphatic esters, optionally substituted aryl esters, silyl esters,activated esters, amides, hydrazides, and the like. Examples of suchester groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl,benzyl, and phenyl ester, wherein each group is optionally substituted.Additional suitable protected carboxylic acids include oxazolines andortho esters.

Protected thiols are well known in the art and include those describedin detail in Greene (1999). Suitable protected thiols further include,but are not limited to, disulfides, thioethers, silyl thioethers,thioesters, thiocarbonates, and thiocarbamates, and the like. Examplesof such groups include, but are not limited to, alkyl thioethers, benzyland substituted benzyl thioethers, triphenylmethyl thioethers, andtrichloroethoxycarbonyl thioester, to name but a few.

Unless otherwise stated, structures depicted herein are also meant toinclude all isomeric (e.g., enantiomeric, diastereomeric, and geometric(or conformational)) forms of the structure; for example, the R and Sconfigurations for each asymmetric center, (Z) and (E) double bondisomers, and (Z) and (E) conformational isomers. Therefore, singlestereochemical isomers as well as enantiomeric, diastereomeric, andgeometric (or conformational) mixtures of the present compounds arewithin the scope of the invention.

Unless otherwise stated, all tautomeric forms of the compounds of theinvention are within the scope of the invention.

Additionally, unless otherwise stated, structures depicted herein arealso meant to include compounds that differ only in the presence of oneor more isotopically enriched atoms. For example, compounds having thepresent structures except for the replacement of hydrogen by deuteriumor tritium, or the replacement of a carbon by a ¹¹C- or ¹³C- or¹⁴C-enriched carbon are within the scope of this invention. Suchcompounds are useful, for example, as analytical tools or probes inbiological assays.

As used herein and in the claims, the singular forms “a”, “an”, and“the” include the plural reference unless the context clearly indicatesotherwise. Thus, for example, a reference to “a compound” includes aplurality of such compounds.

As used herein, the term “in vitro” refers to events that occur in anartificial environment, e.g., in a test tube or reaction vessel, in cellculture, etc., rather than within an organism (e.g., animal, plant,and/or microbe).

As used herein, the term “in vivo” refers to events that occur within anorganism (e.g., animal, plant, and/or microbe).

The phrases “parenteral administration” and “administered parenterally”as used herein have their art-understood meaning referring to modes ofadministration other than enteral and topical administration, usually byinjection, and include, without limitation, intravenous, intramuscular,intraarterial, intrathecal, intracapsular, intraorbital, intracardiac,intradermal, intraperitoneal, transtracheal, subcutaneous, subcuticular,intraarticulare, subcapsular, subarachnoid, intraspinal, andintrasternal injection and infusion.

As used herein, the term “pharmaceutical composition” refers to anactive agent, formulated together with one or more pharmaceuticallyacceptable carriers. In some embodiments, active agent is present inunit dose amount appropriate for administration in a therapeutic regimenthat shows a statistically significant probability of achieving apredetermined therapeutic effect when administered to a relevantpopulation. In some embodiments, pharmaceutical compositions may bespecially formulated for administration in solid or liquid form,including those adapted for the following: oral administration, forexample, drenches (aqueous or non-aqueous solutions or suspensions),tablets, e.g., those targeted for buccal, sublingual, and systemicabsorption, boluses, powders, granules, pastes for application to thetongue; parenteral administration, for example, by subcutaneous,intramuscular, intravenous or epidural injection as, for example, asterile solution or suspension, or sustained-release formulation;topical application, for example, as a cream, ointment, or acontrolled-release patch or spray applied to the skin, lungs, or oralcavity; intravaginally or intrarectally, for example, as a pessary,cream, or foam; sublingually; ocularly; transdermally; or nasally,pulmonary, and to other mucosal surfaces.

As used herein, the phrase “pharmaceutically acceptable” refers to thosecompounds, materials, compositions, and/or dosage forms which are,within the scope of sound medical judgment, suitable for use in contactwith the tissues of human beings and animals without excessive toxicity,irritation, allergic response, or other problem or complication,commensurate with a reasonable benefit/risk ratio.

As used herein, the term “pharmaceutically acceptable carrier” means apharmaceutically-acceptable material, composition or vehicle, such as aliquid or solid filler, diluent, excipient, or solvent encapsulatingmaterial, involved in carrying or transporting the subject compound fromone organ, or portion of the body, to another organ, or portion of thebody. Each carrier must be “acceptable” in the sense of being compatiblewith the other ingredients of the formulation and not injurious to thepatient. Some examples of materials which can serve aspharmaceutically-acceptable carriers include: sugars, such as lactose,glucose and sucrose; starches, such as corn starch and potato starch;cellulose, and its derivatives, such as sodium carboxymethyl cellulose,ethyl cellulose and cellulose acetate; powdered tragacanth; malt;gelatin; talc; excipients, such as cocoa butter and suppository waxes;oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil,olive oil, corn oil and soybean oil; glycols, such as propylene glycol;polyols, such as glycerin, sorbitol, mannitol and polyethylene glycol;esters, such as ethyl oleate and ethyl laurate; agar; buffering agents,such as magnesium hydroxide and aluminum hydroxide; alginic acid;pyrogen-free water; isotonic saline; Ringer's solution; ethyl alcohol;pH buffered solutions; polyesters, polycarbonates and/or polyanhydrides;and other non-toxic compatible substances employed in pharmaceuticalformulations.

The term “pharmaceutically acceptable salt”, as used herein, refers tosalts of such compounds that are appropriate for use in pharmaceuticalcontexts, i.e., salts which are, within the scope of sound medicaljudgment, suitable for use in contact with the tissues of humans andlower animals without undue toxicity, irritation, allergic response andthe like, and are commensurate with a reasonable benefit/risk ratio.Pharmaceutically acceptable salts are well known in the art. Forexample, S. M. Berge, et al. describes pharmaceutically acceptable saltsin detail in J. Pharmaceutical Sciences, 66: 1-19 (1977). In someembodiments, pharmaceutically acceptable salt include, but are notlimited to, nontoxic acid addition salts, which are salts of an aminogroup formed with inorganic acids such as hydrochloric acid, hydrobromicacid, phosphoric acid, sulfuric acid and perchloric acid or with organicacids such as acetic acid, maleic acid, tartaric acid, citric acid,succinic acid or malonic acid or by using other methods used in the artsuch as ion exchange. In some embodiments, pharmaceutically acceptablesalts include, but are not limited to, adipate, alginate, ascorbate,aspartate, benzenesulfonate, benzoate, bisulfate, borate, butyrate,camphorate, camphorsulfonate, citrate, cyclopentanepropionate,digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate,glucoheptonate, glycerophosphate, gluconate, hemisulfate, heptanoate,hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate,lactate, laurate, lauryl sulfate, malate, maleate, malonate,methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate,oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate,phosphate, picrate, pivalate, propionate, stearate, succinate, sulfate,tartrate, thiocyanate, p-toluenesulfonate, undecanoate, valerate salts,and the like. Representative alkali or alkaline earth metal saltsinclude sodium, lithium, potassium, calcium, magnesium, and the like. Insome embodiments, pharmaceutically acceptable salts include, whenappropriate, nontoxic ammonium, quaternary ammonium, and amine cationsformed using counterions such as halide, hydroxide, carboxylate,sulfate.

As used herein, the term “protein” refers to a polypeptide (i.e., astring of at least two amino acids linked to one another by peptidebonds). In some embodiments, proteins include only naturally-occurringamino acids. In some embodiments, proteins include one or morenon-naturally-occurring amino acids (e.g., moieties that form one ormore peptide bonds with adjacent amino acids). In some embodiments, oneor more residues in a protein chain contain a non-amino-acid moiety(e.g., a glycan, etc). In some embodiments, a protein includes more thanone polypeptide chain, for example linked by one or more disulfide bondsor associated by other means. In some embodiments, proteins containl-amino acids, d-amino acids, or both; in some embodiments, proteinscontain one or more amino acid modifications or analogs known in theart. Useful modifications include, e.g., terminal acetylation,amidation, methylation, etc. The term “peptide” is generally used torefer to a polypeptide having a length of less than about 100 aminoacids, less than about 50 amino acids, less than 20 amino acids, or lessthan 10 amino acids. In some embodiments, proteins are antibodies,antibody fragments, biologically active portions thereof, and/orcharacteristic portions thereof.

As used herein, the term “subject” or “test subject” refers to anyorganism to which a provided compound or composition is administered inaccordance with the present invention e.g., for experimental,diagnostic, prophylactic, and/or therapeutic purposes. Typical subjectsinclude animals (e.g., mammals such as mice, rats, rabbits, non-humanprimates, and humans; insects; worms; etc.). In some embodiments, asubject may be suffering from, and/or susceptible to a disease,disorder, and/or condition. In some embodiments, a subject is human.

As used herein, the term “substantially” refers to the qualitativecondition of exhibiting total or near-total extent or degree of acharacteristic or property of interest. One of ordinary skill in thebiological arts will understand that biological and chemical phenomenararely, if ever, go to completion and/or proceed to completeness orachieve or avoid an absolute result. The term “substantially” istherefore used herein to capture the potential lack of completenessinherent in many biological and/or chemical phenomena.

An individual who is “suffering from” a disease, disorder, and/orcondition has been diagnosed with and/or displays one or more symptomsof a disease, disorder, and/or condition

An individual who is “susceptible to” a disease, disorder, and/orcondition is one who has a higher risk of developing the disease,disorder, and/or condition than does a member of the general public. Insome embodiments, an individual who is susceptible to a disease,disorder and/or condition may not have been diagnosed with the disease,disorder, and/or condition. In some embodiments, an individual who issusceptible to a disease, disorder, and/or condition may exhibitsymptoms of the disease, disorder, and/or condition. In someembodiments, an individual who is susceptible to a disease, disorder,and/or condition may not exhibit symptoms of the disease, disorder,and/or condition. In some embodiments, an individual who is susceptibleto a disease, disorder, and/or condition will develop the disease,disorder, and/or condition. In some embodiments, an individual who issusceptible to a disease, disorder, and/or condition will not developthe disease, disorder, and/or condition.

The phrases “systemic administration,” “administered systemically,”“peripheral administration,” and “administered peripherally” as usedherein have their art-understood meaning referring to administration ofa compound or composition such that it enters the recipient's system.

As used herein, the phrase “therapeutic agent” refers to any agent that,when administered to a subject, has a therapeutic effect and/or elicitsa desired biological and/or pharmacological effect. In some embodiments,a therapeutic agent is any substance that can be used to alleviate,ameliorate, relieve, inhibit, prevent, delay onset of, reduce severityof, and/or reduce incidence of one or more symptoms or features of adisease, disorder, and/or condition.

As used herein, the term “therapeutically effective amount” means anamount of a substance (e.g., a therapeutic agent, composition, and/orformulation) that elicits a desired biological response whenadministered as part of a therapeutic regimen. In some embodiments, atherapeutically effective amount of a substance is an amount that issufficient, when administered to a subject suffering from or susceptibleto a disease, disorder, and/or condition, to treat, diagnose, prevent,and/or delay the onset of the disease, disorder, and/or condition. Aswill be appreciated by those of ordinary skill in this art, theeffective amount of a substance may vary depending on such factors asthe desired biological endpoint, the substance to be delivered, thetarget cell or tissue, etc. For example, the effective amount ofcompound in a formulation to treat a disease, disorder, and/or conditionis the amount that alleviates, ameliorates, relieves, inhibits,prevents, delays onset of, reduces severity of and/or reduces incidenceof one or more symptoms or features of the disease, disorder, and/orcondition. In some embodiments, a therapeutically effective amount isadministered in a single dose; in some embodiments, multiple unit dosesare required to deliver a therapeutically effective amount.

As used herein, the term “treat,” “treatment,” or “treating” refers toany method used to partially or completely alleviate, ameliorate,relieve, inhibit, prevent, delay onset of, reduce severity of, and/orreduce incidence of one or more symptoms or features of a disease,disorder, and/or condition. Treatment may be administered to a subjectwho does not exhibit signs of a disease, disorder, and/or condition. Insome embodiments, treatment may be administered to a subject whoexhibits only early signs of the disease, disorder, and/or condition,for example for the purpose of decreasing the risk of developingpathology associated with the disease, disorder, and/or condition.

The expression “unit dose” as used herein refers to an amountadministered as a single dose and/or in a physically discrete unit of apharmaceutical composition. In many embodiments, a unit dose contains apredetermined quantity of an active agent. In some embodiments, a unitdose contains an entire single dose of the agent. In some embodiments,more than one unit dose is administered to achieve a total single dose.In some embodiments, administration of multiple unit doses is required,or expected to be required, in order to achieve an intended effect. Aunit dose may be, for example, a volume of liquid (e.g., an acceptablecarrier) containing a predetermined quantity of one or more therapeuticagents, a predetermined amount of one or more therapeutic agents insolid form, a sustained release formulation or drug delivery devicecontaining a predetermined amount of one or more therapeutic agents,etc. It will be appreciated that a unit dose may be present in aformulation that includes any of a variety of components in addition tothe therapeutic agent(s). For example, acceptable carriers (e.g.,pharmaceutically acceptable carriers), diluents, stabilizers, buffers,preservatives, etc., may be included as described infra. It will beappreciated by those skilled in the art, in many embodiments, a totalappropriate daily dosage of a particular therapeutic agent may comprisea portion, or a plurality, of unit doses, and may be decided, forexample, by the attending physician within the scope of sound medicaljudgment. In some embodiments, the specific effective dose level for anyparticular subject or organism may depend upon a variety of factorsincluding the disorder being treated and the severity of the disorder;activity of specific active compound employed; specific compositionemployed; age, body weight, general health, sex and diet of the subject;time of administration, and rate of excretion of the specific activecompound employed; duration of the treatment; drugs and/or additionaltherapies used in combination or coincidental with specific compound(s)employed, and like factors well known in the medical arts.

As used herein, the terms “effective amount” and “effective dose” referto any amount or dose of a compound or composition that is sufficient tofulfill its intended purpose(s), i.e., a desired biological or medicinalresponse in a tissue or subject at an acceptable benefit/risk ratio. Therelevant intended purpose may be objective (i.e., measurable by sometest or marker) or subjective (i.e., subject gives an indication of orfeels an effect). In some embodiments, a therapeutically effectiveamount is an amount that, when administered to a population of subjectsthat meet certain clinical criteria for a disease or disorder (forexample, as determined by symptoms manifested, diseaseprogression/stage, genetic profile, etc.), a statistically significanttherapeutic response is obtained among the population. A therapeuticallyeffective amount is commonly administered in a dosing regimen that maycomprise multiple unit doses. For any particular pharmaceutical agent, atherapeutically effective amount (and/or an appropriate unit dose withinan effective dosing regimen) may vary, for example, depending on routeof administration, on combination with other pharmaceutical agents. Insome embodiments, the specific therapeutically effective amount (and/orunit dose) for any particular patient may depend upon a variety offactors including the disorder being treated and the severity of thedisorder; the activity of the specific pharmaceutical agent employed;the specific composition employed; the age, body weight, general health,sex and diet of the patient; the time of administration, route ofadministration, and/or rate of excretion or metabolism of the specificpharmaceutical agent employed; the duration of the treatment; and likefactors as is well known in the medical arts. Those of ordinary skill inthe art will appreciate that in some embodiments of the invention, aunit dosage may be considered to contain an effective amount if itcontains an amount appropriate for administration in the context of adosage regimen correlated with a positive outcome.

3. Description of Certain Embodiments of the Invention

In some embodiments, the present invention provides a pharmaceuticalcomposition of a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination.

In some embodiments, the present invention provides a method fortreating a blood cancer in a subject in need thereof, comprisingadministering to the subject a therapeutically effective amount of acompound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination. In some embodiments, a subject is suffering from ablood cancer. In some embodiments, a subject is susceptible to a bloodcancer.

In some embodiments, the present invention provides a method forinhibiting growth of blood cancer cells. In some embodiments, thepresent invention provides a method for inhibiting growth of bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination.

In some embodiments, the present invention provides a method forinhibiting proliferation of blood cancer cells. In some embodiments, thepresent invention provides a method for inhibiting proliferation ofblood cancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination.

In some embodiments, the present invention provides a method forpromoting apoptosis of blood cancer cells. In some embodiments, thepresent invention provides a method for promoting apoptosis of bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination.

In some embodiments, the present invention provides a method forarresting cell cycle in blood cancer cells. In some embodiments, thepresent invention provides a method for arresting cell cycle in bloodcancer cells, comprising administering a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination.

In some embodiments, the present invention provides a method forinducing arrest in G2/M phase in blood cancer cells. In someembodiments, the present invention provides a method for inducing arrestin G2/M phase in blood cancer cells, comprising administering a compoundof formula I:

or a pharmaceutically acceptable salt thereof, wherein each variable isindependently as described in classes and subclasses herein, both singlyand in combination.

As defined generally above, R¹ is —H or —CH₃. In some embodiments, R¹ is—H. In some embodiments, R¹ is —CH₃.

As defined generally above, R² is —OH or —OCH₃. In some embodiments, R²is —OH. In some embodiments, R² is —OCH₃.

As defined generally above, R³ is —H or —OH. In some embodiments, R³ is—H. In some embodiments, R³ is —OH.

In some embodiments, R⁴ is —H, or —Br when R¹ is —CH₃. In someembodiments, R⁴ is —H. In some embodiments, R⁴ is —Br when R¹ is —CH₃.

In some embodiments, a compound of formula I has an IC₅₀ value of about0.02 μM or less for a blood cancer cell line. In some embodiments, acompound of formula I has an IC₅₀ value of about 0.03 μM or less for ablood cancer cell line. In some embodiments, a compound of formula I hasan IC₅₀ value of about 0.04 μM or less for a blood cancer cell line. Insome embodiments, a compound of formula I has an IC₅₀ value of about0.05 μM or less for a blood cancer cell line. In some embodiments, acompound of formula I has an IC₅₀ value of about 0.06 μM or less for ablood cancer cell line. In some embodiments, a compound of formula I hasan IC₅₀ value of about 0.07 μM or less for a blood cancer cell line. Insome embodiments, a compound of formula I has an IC₅₀ value of about0.08 μM or less for a blood cancer cell line. In some embodiments, acompound of formula I has an IC₅₀ value of about 0.09 μM or less for ablood cancer cell line. In some embodiments, a compound of formula I hasan IC₅₀ value of about 0.1 μM or less for a blood cancer cell line. Insome embodiments, a compound of formula I has an IC₅₀ value of about0.15 μM or less for a blood cancer cell line. In some embodiments, acompound of formula I has an IC₅₀ value of about 0.2 μM or less for ablood cancer cell line. In some embodiments, a compound of formula I hasan IC₅₀ value of about 0.3 μM or less for a blood cancer cell line. Insome embodiments, a compound of formula I has an IC₅₀ value of about 0.4μM or less for a blood cancer cell line. In some embodiments, a compoundof formula I has an IC₅₀ value of about 0.5 μM or less for a bloodcancer cell line. In some embodiments, a compound of formula I has anIC₅₀ value of about 0.6 μM or less for a blood cancer cell line. In someembodiments, a compound of formula I has an IC₅₀ value of about 0.7 μMor less for a blood cancer cell line. In some embodiments, a compound offormula I has an IC₅₀ value of about 0.8 μM or less for a blood cancercell line. In some embodiments, a compound of formula I has an IC₅₀value of about 0.9 μM or less for a blood cancer cell line. In someembodiments, a compound of formula I has an IC₅₀ value of about 1 μM orless for a blood cancer cell line. In some embodiments, a compound offormula I has an IC₅₀ value of about 2 μM or less for a blood cancercell line. In some embodiments, a compound of formula I has an IC₅₀value of about 3 μM or less for a blood cancer cell line. In someembodiments, a compound of formula I has an IC₅₀ value of about 4 μM orless for a blood cancer cell line. In some embodiments, a compound offormula I has an IC₅₀ value of about 5 μM or less for a blood cancercell line. In some embodiments, a compound of formula I has an IC₅₀value of about 6 μM or less for a blood cancer cell line. In someembodiments, a compound of formula I has an IC₅₀ value of about 7 μM orless for a blood cancer cell line. In some embodiments, a compound offormula I has an IC₅₀ value of about 8 μM or less for a blood cancercell line. In some embodiments, a compound of formula I has an IC₅₀value of about 9 μM or less for a blood cancer cell line. In someembodiments, a compound of formula I has an IC₅₀ value of about 10 μM orless for a blood cancer cell line.

In some embodiments, an IC₅₀ value is measured at about 48-hour exposureto a compound of formula I (48-hr IC₅₀). In some embodiments, IC₅₀ isdetermined by3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium)(MTS). In some embodiments, IC₅₀ is determined by sulforhodamine B(SRB).

In some embodiments, a blood cancer cell line is U-937. In someembodiments, a blood cancer cell line is CEM. In some embodiments, ablood cancer cell line is Jurkat. In some embodiments, a blood cancercell line is Daudi. In some embodiments, a blood cancer cell line isHL-60. In some embodiments, a blood cancer cell line is CA46.

In some embodiments, a compound of formula I has a lower IC₅₀ for one ormore of blood cancer cell lines, e.g., U-937, CEM, Jurkat, Daudi, HL-60and CA46, than for one or more of non-blood cancer cell lines, e.g.,Hela, A549 and BT549. In some embodiments, a compound of formula I has alower IC₅₀ for each of the U-937, CEM, Jurkat, Daudi, HL-60 and CA46cell lines than for each of Hela, A549 and BT549.

In some embodiments, a compound of formula I has a lower IC₅₀ for bloodcancer cells than normal cells. In some embodiments, a compound offormula I has a lower IC₅₀ for blood cancer cells than for immortalizedlung fibroblast (e.g., IMR 90 cell line).

In some embodiments, a compound of formula I has low hemolytic activity.In some embodiments, a compound of formula I has no hemolytic activityat 333 μM, as measured using the method described for FIG. 2. In someembodiments, a compound of formula I has no hemolytic activity at about300 μM. In some embodiments, a compound of formula I has no hemolyticactivity at about 250 μM. In some embodiments, a compound of formula Ihas no hemolytic activity at about 200 μM. In some embodiments, acompound of formula I has no hemolytic activity at about 150 μM. In someembodiments, a compound of formula I has no hemolytic activity at about100 μM In some embodiments, a compound of formula I has no hemolyticactivity at about 50 μM. In some embodiments, a compound of formula Ishow no or low hemolytic activity, e.g., <10% blood cell hemolysis, at aconcentration 10,000 fold of its IC₅₀ for blood cancer cells, e.g.,U-937, CEM, Jurkat, Daudi, HL-60 or CA46 cell line. In some embodiments,a compound of formula I show no or low hemolytic activity at aconcentration 5,000 fold of its IC₅₀ for blood cancer cells. In someembodiments, a compound of formula I show no or low hemolytic activityat a concentration 1,000 fold of its IC₅₀ for blood cancer cells. Insome embodiments, a compound of formula I show no or low hemolyticactivity at a concentration 500 fold of its IC₅₀ for blood cancer cells.In some embodiments, hemolysis is measured two hours after compoundadministration.

Blood cancers, or hematologic cancers, include cancers of the blood,bone marrow and lymph nodes. In some embodiments, blood cancers includeleukemia, lymphoma and myeloma.

In some embodiments, a blood cancer is leukemia. Leukemia includeslymphocytic leukemia and myelogenous leukemia (also known as myeloid ormyelocytic leukemia). In some embodiments, a blood cancer is lymphocyticleukemia. In some embodiments, a blood cancer is myelogenous leukemia.In some embodiments, leukemia is acute. In some embodiments, leukemia ischronic. In some embodiments, a blood cancer is acute lymphoblasticleukemia (ALL). In some embodiments, a blood cancer is acute myelogenousleukemia (AML). In some embodiments, a blood cancer is chroniclymphocytic leukemia (CLL). In some embodiments, a blood cancer ischronic myelogenous leukemia (CML). In some embodiments, a blood canceris acute monocytic leukemia (AMoL). In some embodiments, a blood canceris acute T-cell leukemia. In some embodiments, a blood cancer is acutepromyelocytic leukemia.

In some embodiments, a blood cancer is lymphoma. Lymphoma includesHodgkin lymphoma and non-Hodgkin lymphoma. In some embodiments, a bloodcancer is Hodgkin lymphoma. In some embodiments, a blood cancer isnon-Hodgkin lymphoma. In some embodiments, a blood cancer is Burkitt'slymphoma.

In some embodiments, a blood cancer is myeloma.

In some embodiments, a blood cancer is selected from acute lymphoblasticleukemia “ALL”, acute lymphoblastic B-cell leukemia, acute lymphoblasticT-cell leukemia, acute myeloblastic leukemia AML”, acute promyelocyticleukemia “APL”, acute monoblastic leukemia, acute erythroleukemicleukemia, acute megakaryoblastic leukemia, acute myelomonocyticleukemia, acute nonlymphocyctic leukemia, acute undifferentiatedleukemia, chronic myelocytic leukemia “CML”, chronic lymphocyticleukemia “CLL”, hairy cell leukemia, multiple myeloma, acute and chronicleukemias, lymphoblastic, myelogenous, lymphocytic and myelocyticleukemias. Lymphomas: , Hodgkin's disease, non-Hodgkin's Lymphoma,Multiple myeloma, Waldenstrom's macroglobulinemia, Heavy chain disease,and Polycythemia vera.

In some embodiments, a compound of formula I is

In some embodiments, a compound of formula I is

In some embodiments, a compound of formula I is

In some embodiments, a compound of formula I is

In some embodiments, a compound of formula I is

In some embodiments, a compound of formula I is

In some embodiments, a provided compound of formula I or itspharmaceutically acceptable salt thereof is administered in acomposition. In some embodiments, a provided compound of formula I orits pharmaceutically acceptable salt thereof is administered in apharmaceutical composition. In some embodiments, a composition in aprovided method is suitable for veterinary or human administration.

A composition can be in any form that allows for the composition to beadministered to a subject. For example, a composition can be in the formof a solid, liquid or gas (aerosol). Typical routes of administrationinclude, without limitation, oral, topical, parenteral, sublingual,rectal, vaginal, ocular, intra-tumor, and intranasal. Parenteraladministration includes subcutaneous injections, intravenous,intramuscular, intrasternal injection or infusion techniques. In someembodiments, a provided compound is administered parenterally. In someembodiments, a provided compound is administered parenterally. In someembodiments, a provided composition is administered intravenously. Insome embodiments, a provided composition is administered intravenously.

Pharmaceutical compositions can be formulated so as to allow a providedcompound to be bioavailable upon administration of the composition to apatient. Compositions can take the form of one or more dosage units,where for example, a tablet can be a single dosage unit, a vial maycontain a single dose for intravenous administration, and a container ofa provided compound in aerosol form can hold a plurality of dosageunits.

Materials used in preparing the pharmaceutical compositions can benon-toxic in the amounts used. It will be evident to those of ordinaryskill in the art that the optimal dosage of the active ingredient(s) inthe pharmaceutical composition will depend on a variety of factors.Relevant factors include, without limitation, the type of animal (e.g.,human), the particular form of a provided compound or composition, themanner of administration, and the composition employed.

A pharmaceutically acceptable carrier or vehicle can be particulate, sothat the compositions are, for example, in tablet or powder form. Thecarrier(s) can be liquid, with the compositions being, for example, anoral syrup or injectable liquid. In addition, the carrier(s) can begaseous or particulate, so as to provide an aerosol composition usefulin, e.g., inhalatory administration. When intended for oraladministration, a composition is preferably in solid or liquid form,where semi-solid, semi-liquid, suspension and gel forms are includedwithin the forms considered herein as either solid or liquid.

As a solid composition for oral administration, a composition can beformulated into a powder, granule, compressed tablet, pill, capsule,chewing gum, wafer or the like form. Such a solid composition typicallycontains one or more inert diluents. In addition, one or more of thefollowing can be present: binders such as carboxymethylcellulose, ethylcellulose, microcrystalline cellulose, or gelatin; excipients such asstarch, lactose or dextrins, disintegrating agents such as alginic acid,sodium alginate, Primogel, corn starch and the like; lubricants such asmagnesium stearate or Sterotex; glidants such as colloidal silicondioxide; sweetening agents such as sucrose or saccharin, a flavoringagent such as peppermint, methyl salicylate or orange flavoring, and acoloring agent.

When a composition is in the form of a capsule, e.g., a gelatin capsule,it can contain, in addition to materials of the above type, a liquidcarrier such as polyethylene glycol, cyclodextrin or a fatty oil.

A composition can be in the form of a liquid, e.g., an elixir, syrup,solution, emulsion or suspension. The liquid can be useful for oraladministration or for delivery by injection. When intended for oraladministration, a composition can comprise one or more of a sweeteningagent, preservatives, dye/colorant and flavor enhancer. In a compositionfor administration by injection, one or more of a surfactant,preservative, wetting agent, dispersing agent, suspending agent, buffer,stabilizer and isotonic agent can also be included.

Liquid compositions, whether they are solutions, suspensions or otherlike form, can also include one or more of the following: sterilediluents such as water for injection, saline solution, preferablyphysiological saline, Ringer's solution, isotonic sodium chloride, fixedoils such as synthetic mono or digylcerides which can serve as thesolvent or suspending medium, polyethylene glycols, glycerin,cyclodextrin, propylene glycol or other solvents; antibacterial agentssuch as benzyl alcohol or methyl paraben; antioxidants such as ascorbicacid or sodium bisulfite; chelating agents such asethylenediaminetetraacetic acid; buffers such as acetates, citrates orphosphates and agents for the adjustment of tonicity such as sodiumchloride or dextrose. A parenteral composition can be enclosed inampoule, a disposable syringe or a multiple-dose vial made of glass,plastic or other material. Physiological saline is an exemplaryadjuvant. An injectable composition is preferably sterile.

The amount of a provided compound that is effective in the treatment ofa particular disorder or condition will depend on the nature of thedisorder or condition, and can be determined by standard clinicaltechniques. In addition, in vitro or in vivo assays can optionally beemployed to help identify optimal dosage ranges. The precise dose to beemployed in the compositions will also depend on the route ofadministration, and the seriousness of the disease or disorder, andshould be decided according to the judgment of the practitioner and eachpatient's circumstances.

Provided compositions comprise an effective amount of a providedcompound such that a suitable dosage will be obtained. In someembodiments, this amount is at least about 0.01% of a provided compoundby weight of the composition. When intended for oral administration,this amount can be varied to range from about 0.1% to about 80% byweight of the composition. In one aspect, oral compositions can comprisefrom about 4% to about 50% of a provided compound by weight of thecomposition. In yet another aspect, a provided composition is preparedso that a parenteral dosage unit contains from about 0.01% to about 2%by weight of a provided compound or composition.

For intravenous administration, a provided composition can comprise fromabout 0.01 to about 100 mg of a provided compound per kg of a subject'sbody weight. In one aspect, the composition can include from about 1 toabout 100 mg of a provided compound per kg of a subject's body weight.In another aspect, the amount administered will be in the range fromabout 0.1 to about 25 mg/kg of body weight of a provided compound.

Generally, dosage of a provided compound administered to a patient istypically about 0.001 mg/kg to about 2000 mg/kg of a subject bodyweight. In one aspect, a dosage administered to a patient is betweenabout 0.01 mg/kg to about 10 mg/kg of a subject's body weight, inanother aspect, a dosage administered to a subject is between about 0.1mg/kg and about 250 mg/kg of a subject's body weight, in yet anotheraspect, a dosage administered to a patient is between about 0.1 mg/kgand about 20 mg/kg of a subject's body weight, in yet another aspect adosage administered is between about 0.1 mg/kg to about 10 mg/kg of asubject's body weight, and in yet another aspect, a dosage administeredis between about 1 mg/kg to about 10 mg/kg of a subject's body weight.In some embodiments, a daily dosage might range from about 1 μg/kg to100 mg/kg or more, depending on the factors mentioned above. Anexemplary dosage to be administered to a patient is in the range ofabout 0.1 to about 10 mg/kg of patient weight.

A provided compound can be administered by any convenient route, forexample by infusion or bolus injection, by absorption through epithelialor mucocutaneous linings (e.g., oral mucosa, rectal and intestinalmucosa, etc.). Administration can be systemic or local. Various deliverysystems are known, e.g., encapsulation in liposomes, microparticles,microcapsules, capsules, etc., and can be used to administer a providedcompound or composition. In certain embodiments, more than one providedcompound or composition is administered to a patient.

In some embodiments, it is desirable to administer one or more providedcompounds or compositions locally to the area in need of treatment. Thiscan be achieved, for example, and not by way of limitation, by localinfusion during surgery; topical application, e.g., in conjunction witha wound dressing after surgery; by injection; by means of a catheter; bymeans of a suppository; or by means of an implant, the implant being ofa porous, non-porous, or gelatinous material, including membranes, suchas sialastic membranes, or fibers. In one embodiment, administration canbe by direct injection at the site (or former site) of a cancer, tumoror neoplastic or pre-neoplastic tissue. In another embodiment,administration can be by direct injection at the site (or former site)of a manifestation of an autoimmune disease.

In certain embodiments, it can be desirable to introduce one or moreprovided compounds or compositions into the central nervous system byany suitable route, including intraventricular and intrathecalinjection. Intraventricular injection can be facilitated by anintraventricular catheter, for example, attached to a reservoir, such asan Ommaya reservoir.

Pulmonary administration can also be employed, e.g., by use of aninhaler or nebulizer, and formulation with an aerosolizing agent, or viaperfusion in a fluorocarbon or synthetic pulmonary surfactant.

In some embodiments, a provided compound or compositions can bedelivered in a controlled release system, such as but not limited to, apump or various polymeric materials can be used. In yet anotherembodiment, a controlled-release system can be placed in proximity of atarget of a provided compound or compositions, e.g., the brain, thusrequiring only a fraction of the systemic dose (see, e.g., Goodson, inMedical Applications of Controlled Release, supra, vol. 2, pp. 115-138(1984)). Other controlled-release systems discussed in the review byLanger (Science 249:1527-1533 (1990)) can be used.

In some embodiments, a carrier is a diluent, adjuvant or excipient, withwhich a provided compound is administered. Such pharmaceutical carrierscan be liquids, such as water and oils, including those of petroleum,animal, vegetable or synthetic origin, such as peanut oil, soybean oil,mineral oil, sesame oil and the like. Carriers can be saline, gumacacia, gelatin, starch paste, talc, keratin, colloidal silica, urea,and the like. In addition, auxiliary, stabilizing, thickening,lubricating and coloring agents can be used. In one embodiment, whenadministered to a patient, provided compounds or compositions andpharmaceutically acceptable carriers are sterile. Water is an exemplarycarrier when a provided compound is administered intravenously. Salinesolutions and aqueous dextrose and glycerol solutions can also beemployed as liquid carriers, particularly for injectable solutions.Suitable pharmaceutical carriers also include excipients such as starch,glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk, silicagel, sodium stearate, glycerol monostearate, talc, sodium chloride,dried skim milk, glycerol, propylene, glycol, water, ethanol and thelike. The present compositions, if desired, can also contain minoramounts of wetting or emulsifying agents, or pH buffering agents.

Provided compositions can take the form of solutions, suspensions,emulsion, tablets, pills, pellets, capsules, capsules containingliquids, powders, sustained-release formulations, suppositories,emulsions, aerosols, sprays, suspensions, or any other form suitable foruse. Other examples of suitable pharmaceutical carriers are described in“Remington's Pharmaceutical Sciences” by E. W. Martin.

In some embodiments, a provided compound or composition is formulated inaccordance with routine procedures as a pharmaceutical compositionadapted for intravenous administration to a subject particularly a humanbeing. In some embodiments, carriers or vehicles for intravenousadministration are sterile isotonic aqueous buffer solutions. Wherenecessary, a provided composition can also include a solubilizing agent.Compositions for intravenous administration can optionally comprise alocal anesthetic such as lignocaine to ease pain at the site of theinjection. Generally, the ingredients are supplied either separately ormixed together in unit dosage form, for example, as a dry lyophilizedpowder or water free concentrate in a hermetically sealed container suchas an ampoule or sachette indicating the quantity of active agent. Wherea provided compound is to be administered by infusion, it can bedispensed, for example, with an infusion bottle containing sterilepharmaceutical grade water or saline. Where a provided compound isadministered by injection, an ampoule of sterile water for injection orsaline can be provided so that the ingredients can be mixed prior toadministration.

Compositions for oral delivery can be in the form of tablets, lozenges,aqueous or oily suspensions, granules, powders, emulsions, capsules,syrups, or elixirs, for example. Orally administered compositions cancontain one or more optionally agents, for example, sweetening agentssuch as fructose, aspartame or saccharin; flavoring agents such aspeppermint, oil of wintergreen, or cherry; coloring agents; andpreserving agents, to provide a pharmaceutically palatable preparation.In some embodiments, where in tablet or pill form, a providedcomposition can be coated to delay disintegration and absorption in thegastrointestinal tract thereby providing a sustained action over anextended period of time. Selectively permeable membranes surrounding anosmotically active driving compound are also suitable for orallyadministered compounds. For example, in these later platforms, fluidfrom the environment surrounding a capsule is imbibed by a drivingcompound, which swells to displace an agent or agent composition throughan aperture. In some embodiments, a delivery platform can provide anessentially zero order delivery profile as opposed to the spikedprofiles of immediate release formulations. A time-delay material suchas glycerol monostearate or glycerol stearate can also be used.

A provided composition can be intended for topical administration, inwhich case the carrier may be in the form of a solution, emulsion,ointment or gel base. If intended for transdermal administration, thecomposition can be in the form of a transdermal patch or aniontophoresis device. Topical formulations can comprise a concentrationof a provided compound of from about 0.05% to about 50% w/v (weight perunit volume of composition), in another aspect, from 0.1% to 10% w/v.

A provided composition can be intended for rectal administration, in theform, e.g., of a suppository which will melt in the rectum and release aprovided compound.

A provided composition can include various materials that modify thephysical form of a solid or liquid dosage unit. For example, a providedcomposition can include materials that form a coating shell around theactive ingredients. The materials that form the coating shell aretypically inert, and can be selected from, for example, sugar, shellac,and other enteric coating agents. Alternatively, the active ingredientscan be encased in a gelatin capsule.

The compositions can consist of gaseous dosage units, e.g., it can be inthe form of an aerosol. In some embodiments, an aerosol is used todenote a variety of systems ranging from those of colloidal nature tosystems consisting of pressurized packages. Delivery can be by aliquefied or compressed gas or by a suitable pump system that dispensesthe active ingredients.

Whether in solid, liquid or gaseous form, a provided composition caninclude a pharmacological agent used in the treatment of cancer, anautoimmune disease or an infectious disease.

A provided pharmaceutical composition may be in the form of a sterileinjectable preparation, such as a sterile injectable aqueous oroleaginous suspension. This suspension may be formulated according tothe known art using those suitable dispersing or wetting agents andsuspending agents which have been mentioned above. The sterileinjectable preparation may also be a sterile injectable solution orsuspension in a non-toxic parenterally acceptable diluent or solvent,such as a solution in 1,3-butane-diol or prepared as a lyophilizedpowder. Among the acceptable vehicles and solvents that may be employedare water, Ringer's solution and isotonic sodium chloride solution. Inaddition, sterile fixed oils may conventionally be employed as a solventor suspending medium. For this purpose any bland fixed oil may beemployed including synthetic mono- or diglycerides. In addition, fattyacids such as oleic acid may likewise be used in the preparation ofinjectables.

Formulations suitable for parenteral administration include aqueous andnon-aqueous sterile injection solutions which may contain anti-oxidants,buffers, bacteriostats and solutes which render the formulation isotonicwith the blood of the intended recipient; and aqueous and non-aqueoussterile suspensions which may include suspending agents and thickeningagents.

Formulations may be packaged in unit-dose or multi-dose containers, forexample sealed ampoules and vials, and may be stored in a freeze-dried(lyophilized) condition requiring only the addition of the sterileliquid carrier, for example water, for injection immediately prior touse. Extemporaneous injection solutions and suspensions are preparedfrom sterile powders, granules and tablets of the kind previouslydescribed. Preferred unit dosage formulations are those containing adaily dose or unit daily sub-dose, as herein above recited, or anappropriate fraction thereof, of the active ingredient.

In some embodiments, the present invention provides veterinarycompositions comprising at least one active ingredient as above definedtogether with a veterinary carrier therefore. Veterinary carriers arematerials useful for the purpose of administering the composition andmay be solid, liquid or gaseous materials which are otherwise inert oracceptable in the veterinary art and are compatible with the activeingredient. These veterinary compositions may be administeredparenterally, orally or by any other desired route.

A provided compound of the invention may be combined in a pharmaceuticalcombination formulation, or dosing regimen as combination therapy, witha second compound having therapeutic properties. A second compound ofthe pharmaceutical combination formulation or dosing regimen preferablyhas complementary activities to a provided compound of the combinationsuch that they do not adversely affect each other.

In some embodiments, a second compound is a chemotherapeutic agent,cytotoxic agent, cytokine, growth inhibitory agent, anti-hormonal, adrug for an autoimmune disease, a drug for an infectious disease, and/orcardioprotectant. Such molecules are suitably present in combination inamounts that are effective for the purpose intended.

A combination therapy may be administered as a simultaneous orsequential regimen. When administered sequentially, the combination maybe administered in two or more administrations. The combinedadministration includes co-administration, using separate formulationsor a single pharmaceutical formulation, and consecutive administrationin either order, wherein preferably there is a time period while both(or all) active agents simultaneously exert their biological activities.

Suitable dosages for co-administered agents are those presently used andmay be lowered due to the combined action (synergy) of the newlyidentified agent and other chemotherapeutic agents or treatments.

A provided combination therapy may provide “synergy” and prove“synergistic”, i.e. the effect achieved when the active ingredients usedtogether is greater than the sum of the effects that results from usingthe compounds separately. A synergistic effect may be attained when theactive ingredients are: (1) co-formulated and administered or deliveredsimultaneously in a combined, unit dosage formulation; (2) delivered byalternation or in parallel as separate formulations; or (3) by someother regimen. When delivered in alternation therapy, a synergisticeffect may be attained when the compounds are administered or deliveredsequentially, e.g. by different injections in separate syringes. Ingeneral, during alternation therapy, an effective dosage of each activeingredient is administered sequentially, i.e. serially, whereas incombination therapy, effective dosages of two or more active ingredientsare administered together.

In some embodiments, the present invention provides methods of treatingcancer. In some embodiments, the present invention provides a method oftreating cancer in a subject suffering therefrom, comprisingadministering to the subject a therapeutically effective amount of aprovided compound. In some embodiments, a provided compound is acompound of formula I or its pharmaceutically acceptable salt thereof.

In some embodiments, a provided compound is administered prior to,concurrently with, or subsequent to, a chemotherapeutic agent. In someembodiments, a chemotherapeutic agent is that with which treatment ofthe cancer has not been found to be refractory. In some embodiments, achemotherapeutic agent is that with which the treatment of cancer hasbeen found to be refractory. In some embodiments, a provided compound isadministered to a patient that has also undergone surgery as treatmentfor the cancer.

In some embodiments, an additional method of treatment is radiationtherapy. In some embodiments, a provided compound or composition isadministered prior to, concurrently with or subsequent to radiation.

In some embodiments, a provided compound or composition is administeredconcurrently with a chemotherapeutic agent or with radiation therapy. Insome embodiments, a chemotherapeutic agent or radiation therapy isadministered prior or subsequent to administration of a providedcompound or composition. In some embodiments, a chemotherapeutic agentor radiation therapy is administered concurrently with administration ofa provided compound or composition. In some embodiments, a providedcompound or composition is administered at least one hour, five hours,12 hours, a day, a week, a month, or several months (e.g., up to threemonths), prior or subsequent to administration of a provided compound orcomposition.

A chemotherapeutic agent can be administered over a series of sessions.Any one or a combination of the chemotherapeutic agents can beadministered. Exemplary chemotherapy drugs are widely known in the art,including but not limited to tubulin-binding drugs, kinase inhibitors,alkylating agents, DNA topoisomerase inhibitors, anti-folates,pyrimidine analogs, purine analogs, DNA antimetabolites, hormonaltherapies, retinoids/deltoids, photodynamic therapies, cytokines,angiogenesis inhibitors, histone modifying enzyme inhibitors, andantimitotic agents. Examples are extensively described in the art,including but not limited to those in PCT Application Publication No.WO2010/025272.

In some embodiments, a provided compound or composition is administeredprior to, concurrently with or subsequent to another polypeptide orprotein. In some embodiments, a polypeptide or protein is a recombinantpolypeptide or protein. Exemplary polypeptides or proteins include butare not limited to cytokines, interferon alfa-2b, interleukin 2,filgrastim, rasburicase, secretin, asparaginase Erwinia chrysanthemi,and ziv-aflibercept. In some embodiments, a polypeptide or proteincomprises an antibody or a fragment of an antibody. In some embodiments,a polypeptide or protein is an antibody or a fragment of an antibody.Examples include but are not limited to rituximab, trastuzumab,tositumomab, alemtuzumab, bevacizumab, cetuximab, panitumumab,ofatumumab, denosumab, ipilimumab, pertuzumab. In some embodiments, apolypeptide or protein is chemically modified. In some embodiments, apolypeptide or protein is conjugated to a drug. In some embodiments, anantibody or an antibody fragment is conjugated to a payload drug,forming an antibody-drug conjugate. In some embodiments, a payload drugis cytotoxic. Exemplary antibody-drug conjugates include but are notlimited to gemtuzumab ozogamicin, brentuximab vedotin, andado-trastuzumab emtansine. In some embodiments, a cancer treatmentcomprises the use of a vaccine. Exemplary vaccines for cancer treatmentare well known in the art, for example but not limited to sipuleucel-T.

With respect to radiation, any radiation therapy protocol can be useddepending upon the type of cancer to be treated. For example, but not byway of limitation, X-ray radiation can be administered; in someembodiments, high-energy megavoltage (radiation of greater that 1 MeVenergy) can be used for deep tumors, and electron beam and orthovoltagex-ray radiation can be used for skin cancers. Gamma-ray emittingradioisotopes, such as radioactive isotopes of radium, cobalt and otherelements, can also be administered.

In some embodiments, methods of treatment of cancer with a providedcompound or composition are provided as an alternative to chemotherapyor radiation therapy where the chemotherapy or the radiation therapy hasproven or can prove too toxic, e.g., results in unacceptable orunbearable side effects, for a subject being treated. A subject beingtreated can, optionally, be treated with another cancer treatment suchas surgery, radiation therapy or chemotherapy, depending on whichtreatment is found to be acceptable or bearable.

In some embodiments, a provided compound or composition can be used inan in vitro or ex vivo fashion, such as for the treatment of certaincancers, including, but not limited to leukemias and lymphomas. In someembodiments, such a treatment involves autologous stem cell transplants.In some embodiments, this can involve a multi-step process in which asubject's autologous hematopoietic stem cells are harvested and purgedof all cancer cells, a subject's remaining bone-marrow cell populationis then eradicated via the administration of a high dose of a providedcompound or composition with or without accompanying high dose radiationtherapy, and the stem cell graft is infused back into the animal.Supportive care is then provided while bone marrow function is restoredand a subject recovers.

In some embodiments, the present invention provides copper-mediatedcross-coupling reaction between thioester and an organostannane reagent.In some embodiments, an organostannane reagent is a stannyl triazonereagent. In some embodiments, an organostannane reagent is stannyl urea.In some embodiments, an organostannane reagent is stannyl guanidine. Insome embodiments, the present invention provides copper-mediatedcross-coupling reaction between thioester and a stannyl triazonereagent. In some embodiments, the metal-mediated cross-coupling reactiondoes not comprise the use of Pd or its salt. In some embodiments, thereaction is carried out with catalytic amount of palladium. In someembodiments, the reaction is carried out without palladium. In someembodiments, the reaction is mediated by a Cu(I) salt. In someembodiments, a Cu(I) salt is Cu(I) diphenylphosphinate (CuDPP). In someembodiments, a Cu(I) salt is Cu(I)-thiophene-2-carboxylate (CuTC). Insome embodiments, a stannyl triazone reagent contains cyclohexyl groups.In some embodiments, a stannyl triazone reagent contains cyclohexylgroups as auxiliary ligands to tin suppress undesired alkyl transfer. Insome embodiments, a thioester has the formula of R⁵C(O)—SR⁹, anorganostannane reagent has the structure of(R)₃SnC(R)₂N(R⁶)—C(X)—N(R⁷)(R⁸), wherein:

-   each of R⁵, R⁶, R⁷, R⁸, R⁹ and R is independently hydrogen or an    optionally substituted group selected from C₁₋₂₀ aliphatic, C₁₋₂₀    heteroalkyl, phenyl, a 3-7 membered saturated or partially    unsaturated carbocyclic ring, an 8-14 membered bicyclic or    polycyclic saturated, partially unsaturated or aryl ring, a 5-6    membered monocyclic heteroaryl ring having 1-4 heteroatoms    independently selected from nitrogen, oxygen, or sulfur, a 3-7    membered saturated or partially unsaturated heterocyclic ring having    1-3 heteroatoms independently selected from nitrogen, oxygen, or    sulfur, a 7-14 membered bicyclic or polycyclic saturated or    partially unsaturated heterocyclic ring having 1-5 heteroatoms    independently selected from nitrogen, oxygen, or sulfur, or an 8-14    membered bicyclic or polycyclic heteroaryl ring having 1-5    heteroatoms independently selected from nitrogen, oxygen, or sulfur;    or:    -   two or more R⁵, R⁶, R⁷, R⁸, R⁹ and R groups are optionally taken        together with their intervening atoms to form an optionally        substituted 3-14 membered, monocyclic or polycyclic, saturated,        partially unsaturated, or aryl ring having, in addition to the        intervening atoms, 0-4 heteroatoms independently selected from        nitrogen, oxygen, or sulfur; and-   X is O or NR.

In some embodiments, X is O. In some embodiments, X is NR, wherein R isas defined above and described herein.

In some embodiments, R⁹ is p-C₆H₄Me. In some embodiments, anorganostannane reagent is (Cy)₃SnCH₂N(R⁶)—C(X)—N(R⁷)(R⁸), wherein eachof R⁶, R⁷ and R⁸ is independently as defined above and described herein.In some embodiments, a product is R⁵C(O)C(R)₂N(R⁶)—C(X)—N(R⁷)(R⁸). Insome embodiments, a product is R⁵C(O)CH₂N(R⁶)—C(X)—N(R⁷)(R⁸). In someembodiments, R⁹ is p-C₆H₄Me, an organostannane reagent is(Cy)₃SnCH₂N(R⁶)—C(X)—N(R⁷)(R⁸), and a product isR⁵C(O)CH₂N(R⁶)—C(X)—N(R⁷)(R⁸). In some embodiments,R⁵C(O)CH₂N(R⁶)—C(X)—N(R⁷)(R⁸) is converted to

Conditions

Suitable conditions for performing provided methods or preparingprovided compounds may employ one or more solvents. In certainembodiments, one or more organic solvents are used. Examples of suchorganic solvents include, but are not limited to, hydrocarbons such asbenzene, toluene, and pentane, halogenated hydrocarbons such asdichloromethane and chloroform, or polar aprotic solvents, such asethereal solvents including ether, tetrahydrofuran (THF), or dioxanes,or protic solvents, such as alcohols, or mixtures thereof. In someembodiments, a solvent is substituted hydrocarbons. In some embodiments,a solvent is MeNO₂. In some embodiments, a solvent is EtNO₂. In certainembodiments, one or more solvents are deuterated. In some embodiments, asingle solvent is used. In certain embodiments, a solvent is benzene. Incertain embodiments, a solvent is ether. In some embodiments, a solventcomprises a nitrile group. In some embodiments, a solvent isacetonitrile.

In some embodiments, mixtures of two or more solvents are used, and insome cases may be preferred to a single solvent. In certain embodiments,the solvent mixture is a mixture of an ethereal solvent and ahydrocarbon. Exemplary such mixtures include, for instance, anether/benzene mixture. Solvent mixtures may be comprised of equalvolumes of each solvent or may contain one solvent in excess of theother solvent or solvents. In certain embodiments wherein a solventmixture is comprised of two solvents, the solvents may be present in aratio of about 20:1, about 10:1, about 9:1, about 8:1, about 7:1, about6:1, about 5:1, about 4:1, about 3:1, about 2:1, or about 1:1. Incertain embodiments wherein a solvent mixture comprises an etherealsolvent and a hydrocarbon, the solvents may be present in a ratio ofabout 20:1, about 10:1, about 9:1, about 8:1, about 7:1, about 6:1,about 5:1, about 4:1, about 3:1, about 2:1, or about 1:1 etherealsolvent:hydrocarbon. In certain embodiments, the solvent mixturecomprises a mixture of ether and benzene in a ratio of about 5:1. One ofskill in the art would appreciate that other solvent mixtures and/orratios are contemplated herein, that the selection of such other solventmixtures and/or ratios will depend on the solubility of species presentin the reaction (e.g., substrates, additives, etc.), and thatexperimentation required to optimized the solvent mixture and/or ratiowould be routine in the art and not undue.

In some embodiments, a solvent is water. In some embodiments, a solventis water. In some embodiments, a mixture of water with one or more othersolvents is used.

Suitable conditions, in some embodiments, employ ambient temperatures.In some embodiments, a suitable temperature is about 15° C., about 20°C., about 25° C., or about 30° C. In some embodiments, a suitabletemperature is from about 15° C. to about 25° C. In certain embodiments,a suitable temperature is about 20° C., 21° C., 22° C., 23° C., 24° C.,or 25° C.

In certain embodiments, a provided method is performed at elevatedtemperature. In some embodiments, a suitable temperature is from about25° C. to about 110° C. In certain embodiments, a suitable temperatureis from about 40° C. to about 100° C., from about 50° C. to about 100°C., from about 60° C. to about 100° C., from about 70° C. to about 100°C., from about 80° C. to about 100° C., or from about 90° C. to about100° C. In some embodiments, a suitable temperature is about 80° C. Insome embodiments, a suitable temperature is about 30° C. In someembodiments, a suitable temperature is about 40° C. In some embodiments,a suitable temperature is about 50° C. In some embodiments, a suitabletemperature is about 60° C. In some embodiments, a suitable temperatureis about 70° C. In some embodiments, a suitable temperature is about 80°C. In some embodiments, a suitable temperature is about 90° C. In someembodiments, a suitable temperature is about 100° C. In someembodiments, a suitable temperature is about 110° C.

In certain embodiments, a provided method is performed at temperaturelower than ambient temperatures. In some embodiments, a suitabletemperature is from about −100° C. to about 10° C. In certainembodiments, a suitable temperature is from about −80° C. to about 0° C.In certain embodiments, a suitable temperature is from about −70° C. toabout 10° C. In certain embodiments, a suitable temperature is fromabout −60° C. to about 10° C. In certain embodiments, a suitabletemperature is from about −50° C. to about 10° C. In certainembodiments, a suitable temperature is from about −40° C. to about 10°C. In certain embodiments, a suitable temperature is or from about −30°C. to about 10° C. In some embodiments, a suitable temperature is below0° C. In some embodiments, a suitable temperature is about −100° C. Insome embodiments, a suitable temperature is about −90° C. In someembodiments, a suitable temperature is about −80° C. In someembodiments, a suitable temperature is about −70° C. In someembodiments, a suitable temperature is about −60° C. In someembodiments, a suitable temperature is about −50° C. In someembodiments, a suitable temperature is about −40° C. In someembodiments, a suitable temperature is about −30° C. In someembodiments, a suitable temperature is about −20° C. In someembodiments, a suitable temperature is about −10° C. In someembodiments, a suitable temperature is about 0° C. In some embodiments,a suitable temperature is about 10° C.

In some embodiments, a provided method is performed at differenttemperatures. In some embodiments, temperature changes in a providedmethod. In some embodiments, a provided method involves temperatureincrease from a lower suitable temperature to a higher suitabletemperature. In some embodiments, a provided method comprisestemperature increase from about −80° C., about −70° C., about −60° C.,about −50° C., about −40° C., about −30° C., about −20° C., about −10°C., and about 0° C. to about 0° C., about 10° C., about 20° C., ambienttemperature, about 22° C., about 25° C., about 30° C., about 40° C.,about 50° C., about 60° C., about 70° C., about 80° C., about 90° C.,about 100° C. and about 110° C. In some embodiments, a provided methodcomprises temperature increase from about −30° C. to 22° C. In someembodiments, a provided method comprises temperature decrease from ahigher suitable temperature to a lower suitable temperature. In someembodiments, a provided method comprises temperature increase from about110° C., about 100° C., about 90° C., about 80° C., about 70° C., about60° C., about 50° C., about 40° C., about 30° C., about 25° C., about22° C., ambient temperature, about 20° C., about 10° C., and about 0° C.to about 0° C., about −10° C., about −20° C., about −30° C., about −40°C., about −50° C., about −60° C., about −70° C., about −80° C., about−90° C., and about −100° C.

Suitable conditions typically involve reaction times of about 1 minuteto about one or more days. In some embodiments, the reaction time rangesfrom about 0.5 hour to about 20 hours. In some embodiments, the reactiontime ranges from about 0.5 hour to about 15 hours. In some embodiments,the reaction time ranges from about 1.0 hour to about 12 hours. In someembodiments, the reaction time ranges from about 1 hour to about 10hours. In some embodiments, the reaction time ranges from about 1 hourto about 8 hours. In some embodiments, the reaction time ranges fromabout 1 hour to about 6 hours. In some embodiments, the reaction timeranges from about 1 hour to about 4 hours. In some embodiments, thereaction time ranges from about 1 hour to about 2 hours. In someembodiments, the reaction time ranges from about 2 hours to about 8hours. In some embodiments, the reaction time ranges from about 2 hoursto about 4 hours. In some embodiments, the reaction time ranges fromabout 2 hours to about 3 hours. In certain embodiments, the reactiontime is about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12, 24, 48, 96 or120 hours. In certain embodiments, the reaction time is about 1 hour. Incertain embodiments, the reaction time is about 2 hours. In certainembodiments, the reaction time is about 3 hours. In certain embodiments,the reaction time is about 4 hours. In certain embodiments, the reactiontime is about 5 hours. In certain embodiments, the reaction time isabout 6 hours. In some embodiments, the reaction time is about 12 hours.In some embodiments, the reaction time is about 24 hours. In someembodiments, the reaction time is about 48 hours. In some embodiments,the reaction time is about 96 hours. In some embodiments, the reactiontime is about 120 hours. In certain embodiments, the reaction time isless than about 1 hour. In certain embodiments, the reaction time isabout 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, or 55 minutes. In someembodiments, the reaction time is about 5 minutes. In some embodiments,the reaction time is about 10 minutes. In some embodiments, the reactiontime is about 15 minutes. In some embodiments, the reaction time isabout 20 minutes. In some embodiments, the reaction time is about 25minutes. In some embodiments, the reaction time is about 30 minutes. Insome embodiments, the reaction time is about 35 minutes. In someembodiments, the reaction time is about 40 minutes. In some embodiments,the reaction time is about 100 minutes. In some embodiments, thereaction time is about 110 minutes. In some embodiments, the reactiontime is about 200 minutes. In some embodiments, the reaction time isabout 300 minutes. In some embodiments, the reaction time is about 400minutes.

In some embodiments, a provided method requires an amount of a compoundwhich promotes a reaction, such that the loading is from about 0.001 mol% to about 20 mol % of the compound relative to substrate. In certainembodiments, the compound is used in an amount of between about 0.001mol % to about 10 mol %. In certain embodiments, the compound is used inan amount of between about 0.001 mol % to about 6 mol %. In certainembodiments, the compound is used in an amount of between about 0.001mol % to about 5 mol %. In certain embodiments, the compound is used inan amount of between about 0.001 mol % to about 4 mol %. In certainembodiments, the compound is used in an amount of between about 0.001mol % to about 3 mol %. In certain embodiments, the compound is used inan amount of between about 0.001 mol % to about 1 mol %. In certainembodiments, the compound is used in an amount of between about 0.001mol % to about 0.5 mol %. In certain embodiments, the compound is usedin an amount of between about 0.001 mol % to about 0.2 mol %. In certainembodiments, the compound is used in an amount of about 0.001 mol %,0.002 mol %, 0.005 mol %, 0.01 mol %, 0.02 mol %, 0.03 mol %, 0.04 mol%, 0.05 mol %, 0.1 mol %, 0.2 mol %, 0.5 mol %, 1 mol %, 2 mol %, 3 mol%, 4 mol %, 5 mol %, 6 mol %, 7 mol %, 8 mol %, 9 mol %, or 10 mol %. Insome embodiments, the compound is used in an amount of about 0.0002%mol. In some embodiments, the compound is used in an amount of about0.01% mol. In some embodiments, the compound is used in an amount ofabout 3% mol.

In some embodiments, a method of the present invention requires anamount of solvent such that the concentration of the reaction is betweenabout 0.01 M and about 1 M. In some embodiments, the concentration ofthe reaction is between about 0.01 M and about 0.5 M. In someembodiments, the concentration of the reaction is between about 0.01 Mand about 0.1 M. In some embodiments, the concentration of the reactionis between about 0.01 M and about 0.05 M. In some embodiments, theconcentration of the reaction is about 0.01 M. In some embodiments, theconcentration of the reaction is about 0.02 M. In some embodiments, theconcentration of the reaction is about 0.03 M. In some embodiments, theconcentration of the reaction is about 0.04 M. In some embodiments, theconcentration of the reaction is about 0.05 M. In some embodiments, theconcentration of the reaction is about 0.1 M. In some embodiments, theconcentration of the reaction is about 0.3 M.

In some embodiments, a method of the present invention is performed atambient pressure. In some embodiments, a method of the present inventionis performed at reduced pressure. In some embodiments, a method of thepresent invention is performed at a pressure of less than about 20 torr.In some embodiments, a method of the present invention is performed at apressure of less than about 15 torr. In some embodiments, a method ofthe present invention is performed at a pressure of less than about 10torr. In some embodiments, a method of the present invention isperformed at a pressure of about 9, 8, 7, 6, 5, 4, 3, 2, or 1 torr. Incertain embodiments, a method of the present invention is performed at apressure of about 7 torr. In certain embodiments, a method of thepresent invention is performed at a pressure of about 1 torr.

In some embodiments, a method of the present invention is performed atincreased pressure. In some embodiments, a method of the presentinvention is performed at greater than about 1 atm. In some embodiments,a method of the present invention is performed at greater than about 2atm. In some embodiments, a method of the present invention is performedat greater than about 3 atm. In some embodiments, a method of thepresent invention is performed at greater than about 5 atm. In someembodiments, a method of the present invention is performed at greaterthan about 10 atm. In some embodiments, a method of the presentinvention is performed at about 2 atm. In some embodiments, a method ofthe present invention is performed at about 3 atm. In some embodiments,a method of the present invention is performed at about 5 atm. In someembodiments, a method of the present invention is performed at about 10atm.

In some embodiments, a provided method provides chemoselectivity. Insome embodiments, a desired product is produced in greater than about50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%,96%, 97% 98%, 99% or 99.5% selectivity.

In some embodiments, a provided method provides stereoselectivity. Insome embodiments, a desired stereoisomer is produced in greater thanabout 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%,95%, 96%, 97% 98%, 99% or 99.5% selectivity. In some embodiments, aprovided method provides diastereoselectivity. In some embodiments, aprovided method provides diastereoselectivity. In some embodiments, adesired diastereomer is produced in greater than about 50%, 55%, 60%,65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97% 98%, 99%or 99.5% selectivity. In some embodiments, a provided method providesenantioselectivity. In some embodiments, a desired enantiomer isproduced in greater than about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%,90%, 91%, 92%, 93%, 94%, 95%, 96%, 97% 98%, 99% or 99.5% selectivity.

It will be appreciated that, in certain embodiments, each variablerecited is as defined above and described in embodiments, herein, bothsingly and in combination.

EXEMPLIFICATION

The present invention recognizes, among other things, that there is acontinuing demand for compounds, compositions and methods for treatingvarious diseases, including blood cancers. In some embodiments, thepresent invention provides such compounds, compositions and methods. Insome embodiments, the present invention provides methods for treatingblood cancers. Exemplary but non-limiting examples are described herein.

The foregoing has been a description of certain non-limiting embodimentsof the invention. Accordingly, it is to be understood that theembodiments of the invention herein described are merely illustrative ofthe application of the principles of the invention. Reference herein todetails of the illustrated embodiments is not intended to limit thescope of the claims.

The agelastatins are a family of cytotoxic pyrrole-imidazole alkaloidsexhibiting a unique tetracyclic framework with four contiguousstereogenic centers on the carbocyclic C-ring.

The structures of (−)-agelastatins A-F′ (1-6). Herein, among otherthings, Applicants provide a detailed account of enantioselective totalsynthesis of certain exemplary compounds and the development of a keymethodology for the synthesis of imidazol-2-one and 2-aminoimidazoles.Applicants also provided exemplary data demonstrating that providedcompounds are particularly useful for treating blood cancers.

One retrosynthetic analysis of (−)-agelastatin A (1) is shown inScheme 1. Ionization of the C5-hydroxyl of 1 followed by thedisconnection of the strategic C4-C8 bond revealed the N-acyliminium ion8. The N-acyliminium ion 8 could be derived from the correspondingC8-hydroxyl derivative, pre-agelastatin A (9), which would be accessedfrom the tricycle 10 through a late-stage C8-oxidation. This analysiswas distinct from prior biosynthetic hypotheses in that: a) C4 served asa nucleophile adding to an electrophilic C8; b) the C-ring formationoccurred post B-ring formation; c) stereochemical information at C7 ofpre-agelastatin A was used to set the C4-, C5-, and C8-stereocenters of(−)-agelastatin A (1).

Keto-triazones could be used for the formation of the C4-C8 bond (Scheme2). C-ring could be generated via nucleophilic attack of a C4-enol to aC8 electrophilic derivative of ketone 12 after C8-oxidation. In thisapproach, the AB-bicyclic structure of ketone 12 could be introduced viaan intramolecular conjugate addition of N12 in mane 13 followed by anoxidative aromatization. L-proline could be used to introduce the C7stereochemistry of intermediate 12.

The above synthetic approach to 1 commenced with a Mitsunobu reactioninvolving L-proline derivative 14 and allylic alcohol 15 followed byDess-Martin periodinane (DMP) C5-oxidation to give enone 16 in 73% yieldover two steps (Scheme 3). Exposure of carbamate 16 to trifluoroaceticacid resulted in the unveiling of the N12 and spontaneous intramolecularconjugate addition to afford pyrrolidine 17 in 85% yield as a 13:1mixture of diastereomers at C7 (major diastereomer shown). Without theintention to be limited by theory, this modest level ofdiastereoselection hinted at possible further refinement of thisapproach for asymmetric synthesis of lactam 18 based on theC11-stereochemistry of enone 16. For the key C-ring cyclization,sequential treatment of ketone 17 with DMP gave the correspondingpyrrole derivative (42% yield), not wishing to be limited by theory,possibly through oxidation of the C11-enol tautomer, followed byN9-desulfonylation to afford the desired lactam 18 in 84% yield.

The oxidation of C8 to generate the necessary electrophile 19 (Scheme 3)proved difficult. α-Oxidation of amides is a challenging process. Afterexamining a wide range of conditions, it was found that treatment oflactam 18 with N-t-butylbenzenesulfinimidoyl chloride in the presence ofDBU gave rise to the enamide 20 in 20% yield along with 20% recovery oflactam 18. Indeed, when ketone 18 was dissolved in methanol-d₄ in thepresence of DBU, complete deuterium incorporation at C4 occurred in lessthan a minute. Without the intention to be limited by theory, the morefacile oxidation of the lactam 18 at positions other than C8, and afavorable tautomerization of acylimine 19 to the highly stable bicycle20 (Scheme 3, arrow B) seemed to prevent the desired formation of theC4-C8 bond (Scheme 3, arrow A).

First-Generation Total Synthesis

Another approach to the desired bicyclic hemiaminal ether 21 was thepartial reduction of C8-carbonyl of imide 23 (Scheme 4). For theformation of the key C4-C8 bond, the imidazolone heterocycle could beused as a nucleophile.

Treatment of the known methyl ester 24 with benzylamine and methoxyamineresulted in the formation of imides 25a and 25b in 86% and 48% yield,respectively (Scheme 5). Each of these imides was obtained as aracemate, without the intention to be limited by theory, reflecting thefacile deprotonation of the acidic C7 proton. Imides 25a and 25b werereadily reduced with L-selectride and subsequent treatment withp-toluenesulfonic acid yielded hemiaminal ethers 26a and 26b in 55% and46% yield (two steps), respectively. The addition of an α-lithiatedtriazone inter mediate, prepared by treatment of triazone 27 withs-butyllithium, to methyl ester (±)-26a gave ketone (±)-28 in 70% yield.Exposure of triazone (±)-28 to methanolic hydrogen chloride solution ledto spontaneous condensative cyclization to form the imidazolone D-ringin 66% yield (Scheme 5).

Imidazolone (±)-29 was then treated with scandiumtrifluoromethanesulfonate (Sc(OTf)₃) to induce the acyliminium ionformation and subsequent introduction of the C-ring; however, theC8-hydroxy hemiaminal product (±)-30, isolated in 36% yield, andpyrrolopyrazinone 31 (<5% yield) were the only observed products (Scheme6). When hemiaminal (±)-30 was exposed to dichloromethane andtrifluoroacetic acid (TFA) mixture, pyrrolopyrazinone 31 was obtained inquantitative yield. While not wishing to be limited by theory,Applicants note that these results suggested that the acyliminium ionintermediate was transiently formed, but was not effectively trapped bythe C4 nucleophile. In an attempt to minimize tautomerization of theacyliminium ion under milder, acid-free reaction conditions, a sulfoxidegroup was planned to be introduced at the C8 position. Thus, imidazolone(±)-29 was treated with ethanethiol in trifluoroacetic acid anddichloromethane mixture to give sulfide (±)-32 (95%), which was oxidizedto sulfoxide (±)-33 in 55% yield upon treatment with sodium periodate(6:4 dr). However, heating a solution of sulfoxide (±)-33 inacetonitrile resulted in the exclusive formation of pyrrolopyrazinone 31(Scheme 6).

The keto-triazone (±)-34, upon sequential treatment with samarium iodide(73% yield) followed by solvolysis in aqueous hydrochloric acid andmethanol mixture, afforded the imidazolone (±)-35 (67% yield, Scheme 7).When imidazolone (±)-35 was treated with TFA-water mixture inacetonitrile, the elimination of methanol occurred to givepyrrolopyrazinone 36 in 95% yield (Scheme 7).

Without the intention to be limited by theory, the formation ofpyrrolopyrazinone 36 could be a result of rapid C7-deprotonation of theC8-iminium ion intermediate to generate the conjugated bicycle prior tothe trapping of C8-electrophile with C4-nucleophile (Scheme 7).Substrate modifications that would lower the kinetic acidity of theproton at C7 and provide greater opportunity for the formation of thedesired C4-C8 bond were tested. Not wishing to be limited by theory,Applicants reasoned that the allylic strain between the C13-bromide andthe C6-methylene, present in all agelastatins, might hinder thistautomerization event. Comparison of the calculated minimum energyconformation of the acyliminium ion derived from C8-ionization of 35 andbrominated acyliminium ion 8 (Scheme 1) revealed that the H7 ofintermediate 8 is ˜22° further away from ideal conformation foracidification as compared to that of the nonbrominated acyliminiun ion.Without the intention to be limited by theory, Applicants noted that theC7-proton of C13-brominated acyliminium ion 8 would be less susceptibleto deprotonation as the overlap of C7-H7 σ-orbital with C8-N9 π*-orbitalwould be less than that of the nonbrominated acyliminium ion, and thatthe lowered kinetic acidity of H7 in the C13-brominated acyliminium ionintermediate 8 would provide greater prospect to trap theC8-electrophilic center with C4-nucleophile before the undesiredH7-deprotonation.

For the introduction of the bromide at C13, keto-triazone 34 was treatedwith N-bromosuccinimide (NBS) to give bromopyrrole 37 in 45% yield(Scheme 8). Samarium iodide-mediated reduction of N-methoxylactam 37(64% yield) followed by treatment with aqueous hydrogen chloride inmethanol afforded (±)-O-methyl-pre-agelastatin A (39) in 65% yield. When(±)-O-methyl-pre-agelastatin A (39) was treated with TFA and water inacetonitrile, (±)-agelastatin A (1) and (±)-di-epi-agelastatin A (40)were obtained as a 2:1 mixture in 47% combined yield. Careful monitoringof this transformation revealed that (±)-4,5-di-epi-agelastatin A (40)was the kinetic product, which equilibrated to the thermodynamicallyfavored (±)-agelastatin A (1). With confirmation of the key step athand, the synthesis of (±)-O-methyl-pre-agelastatin A (39) could bestreamlined via a fragment assembly that would obviate the need for theN-methoxy substitution of the B-ring lactam.

Second Generation of Total Sythesis

Without the intention to be limited by theory, Applicants rationalizedthat a facile and reversible enolization at C7 caused the racemizationof imide derivatives 25a and 25b (Scheme 5), and envisioned that thebromination at C13 of these imides would lower the kinetic acidity oftheir H7 and potentially minimize erosion of their enantiomeric excess.Amide (+)-41 could be obtained in two steps from a known pyrrolederivative upon bromination and acylation. When amide (+)-41 wasdissolved in methanol-d₄ facile B-ring cyclization was observed.Importantly, it took 1 h for the C7-methine to show 52% deuteriumincorporation and an additional 2 hours to show complete deuteriumincorporation (Scheme 9), which could provide a small window ofopportunity to intercept the imide carbonyl C8 via a rapid reductionbefore racemization.

Exposure of methyl ester (+)-41 to sodium borohydride in methanol at 0°C. (Scheme 10) led to cyclization and reduction of the resulting imideto afford an α-hydroxyamide intermediate. Subsequent addition ofp-toluenesalfonic acid monohydrate to the reaction mixture enabled amethanolysis reaction to directly give bicycle (+)-44 in 90% (>10g-scale) and 99% ee.

While the C13-bromide served critical roles in both suppressingC7-racemization (Scheme 10) and enabling the key C-ring cyclization(Schemes 8), it was incompatible with the addition of the lithiatedtriazone to methyl ester (+)-44 as detailed in Scheme 5. When the samelithiated triazone was exposed to methyl ester (±)-44, the reaction wasplagued by the undesired reactivity between the C13-bromide and theorganolithium species. The corresponding Grignard, organocerium,organocuprate, and organozinc derivatives failed to add to methyl ester(+)-44. However, Applicants found that the organocerium triazonederivative added smoothly to an aldehyde variant of ester (+)-44 for theintroduction of the C4-C5 bond (64% yield), enabling the secondgeneration total synthesis of (−)-agelastatins A (1) and B (2).Following the successful access to enantiomerically enriched alkaloids(−)-1 and (−)-2 via strategic introduction of C13-bromide at an earlystage of the synthesis, a more concise strategy was pursued for theunion of the desired triazone fragment and the readily availablebicyclic ester (+)-44.

Third Generation of Total Synthesis

As an example, Applicants described herein an efficient metal-mediatedcross-coupling reaction between thioester (+)-45, derived from methylester (+)-44 in one step, and a stannyl triazone derivative (Table 1).Under the previously reported reaction conditions, thioester (+)-45 andtriazone 46 in the presence of Pd₂(dba)₃, Cu(I) diphenylphosphinate(CuDPP), and triethyl phosphite in THF at 23° C. failed to deliver thedesired product (Table 1, entry 1). Substitution of triethyl phosphitewith SPhos also showed no improvement (Table 1, entry 2). Surprisingly,upon treatment of thioester (+)-45 and triazone 46 with a catalyticamount of Pd(PPh₃)₄ and stoichiometric amount of CuDPP at 50° C., thedesired coupled product (+)-48 was obtained in 50% yield. Under theseconditions, byproduct 49a, resulting from an undesired transfer of an-butyl group from the stannane 46, was also formed in 50% yield (Table1, entry 3). Unexpectedly, by switching the copper additive toCu(I)-thiophene-2-carboxylate (CuTC), the formation of the desiredcoupled product (+)-48 (60% yield) was favored over the undesiredbyproduct 49a (40% yield, Table 1, entry 4). Even more surprisingly,this transformation could be carried out with equal efficiency withoutthe palladium catalyst (Table 1, entry 5). To suppress the undesiredalkyl transfer, a stannyltriazone substrate 47 containing cyclohexylgroups was employed as auxiliary ligands to the tin. Surprisingly, whenthioester (+)-45 and triazone 47 were treated with CuTC (1.5 equiv) at50° C., the desired ketone (+)-48 was formed exclusively in 96% yieldand 99% ee (>5 g-scale, Table 1, entry 6).

TABLE 1 Copper-mediated cross-coupling between thioester (+)-45 andstannyl triazone derivatives.

temp time (+)-48 49 entry triazone catalyst (mol %) additive (equiv)(C.) (h) (%) (%) 1 46 Pd₂(dba)₃ (5) CuDPP (2.4) 23 24 — — P(OEt)₃ (0.4)2 46 Pd₂(dba)₃ (10) CuDPP (2.4) 23 24 — — SPhos (0.8) 3 46 Pd(PPh₃)₄(10) CuDPP (2.4) 50 2 50 50 4 46 Pd(PPh₃)₄ (9) CuTC (2.4) 50 2 60 40 546 — CuTC (2.4) 50 1 63 36 6 47 — CuTC (1.5) 50 0.5 96a  — a. Reactionwas performed in >5 g scale. Tol = C₆H₄—p—Me, c-Hx = cyclohexyl.

Having established a reliable method to access ketone (+)-48, Applicantsnext optimized the final steps leading to (−)-agelastatin A (1).Keto-triazone (+)-48 was most efficiently converted to(+)-O-methyl-pre-agelastatin A (39) upon exposure to methanolic hydrogenchloride at 65° C. (89% yield, 99% ee, Scheme 11). Additionally,treatment of (+)-O-methyl-pre-agelastatin A (39) with aqueousmethanesulfonic acid at 100° C., followed by introduction of methanol tothe resulting mixture of (−)-agelastatin A (1) and(−)-di-epi-agelastatin A (40), afforded (−)-agelastatin A (1) in 49%yield (99% ee, >1 g-scale) along with (−)-O-methyl-di-epi-agelastatin A(50, 22% yield, Scheme 11). Not only could diastereomer 50 be readilyseparated by flash column chromatography, but its resubmission to theabove protocol provided another batch of (−)-agelastatin A (1) in 66%yield along with recovered (−)-50 in 30% yield. While treatment of anaqueous tetrahydrofuran solution of (−)-agelastatin A (1) with NBS and2,6-di-t-butyl-4-methylpyridine (DTBMP) efficiently afforded(−)-agelastatin B (2) in 84% yield, the exposure of a methanolicsolution of (−)-1 to amberlyst 15 resin provided (−)-agelastatin E (5)in 96% yield.

Concerning the synthesis of (−)-agelastatin C (3), a wide range ofoxidants tested was found to be ineffective for the direct oxidation ofthe C4-methine of (−)-agelastatin A (1). A strategy was devised based onthe oxidation of (−)-dehydroagelastatin A (51, Scheme 11).(−)-O-methyl-di-epi-agelastatin A (50) was readily converted to(−)-dehydroagelastatin A (51) upon heating in pyridine at 115° C. in 95%yield (Scheme 11). Treatment of (−)-dehydroagelastatin A (51) withdimethyldioxirane (DMDO) provided (−)-di-epi-agelastatin C (52) in 98%yield, via oxidation on the convex face. Notably, heating an aqueoussolution of (−)-di-epi-agelastatin C (52) in the presence of amberlyst15 resin afforded (−)-agelastatin C (3) in 41% yield along withrecovered (−)-di-epi-agelastatin C (52, 42% yield).

The copper-mediated cross-coupling reaction of thioester andorganostannane enabled an efficient synthesis of(+)-O-methyl-pre-agelastatin D (53, Scheme 12) as described in thefollowing section (Table 2), and consequently the first synthetic sampleof (−)-agelastatin D (4). When (+)-O-methyl-pre-agelastatin D (53) washeated in aqueous acidic solution followed by methanol treatment,(−)-agelastatin D (4) was obtained in 26% yield along with(−)-O-methyl-di-epi-agelastatin D (54, 9% yield, Scheme 12). Thereaction also provided compound 55 (20% yield) and compound 56 (20%yield).

Heating an aqueous acidic solution of 13-desbromoenamide 57 resulted inclean formation of tetracycle 56 (46%). Without the intention to belimited by theory, Applicants propose that byproduct 56 may be formedvia protodebromination at C13, followed by enamide formation, and C4 toC13 cyclization; a mechanism involving protodebromination after theC4-C13 cyclization might also be possible.

Without the intention to be limited by theory,Applicants propose thatthe formation of byproducts 55 and 56 may be consistent with the lowerC4-nucleophilicity of (+)-O-methyl-pre-agelastatin D (53) compared tothat of (+)-O-methyl-pre-agelastatin A (39): monitoring of the rates ofdeuterium incorporation at C4 position of (+)-O-methyl-pre-agelastatinsA (39) and D (53), respectively, revealed that deuterium incorporationat C4 occurred ten times faster in (+)-39 as compared to (+)-53(k₁=3.094×10⁻⁵/sec, k₂=3.028×10⁻⁶/sec), consistent with its moreefficient C4-C8 bond formation (Scheme 14). Not wishing to be limited bytheory, Applicants note that the scarcity of natural (−)-agelastatin D(4) compared to other N1-methyl agelastatin alkaloids is consistent withthis observation on the lower efficiency of the desired cyclization with53 as compared to 39.

Copper-Mediated Cross-Coupling Reaction of Thioesters andOrganostannanes—Additional Examples

The copper-mediated cross-coupling reactions between thioester, forexample, 45 and organostannanes, for example, 46 and 47 (Table 1) hasbroad scope and applications (Scheme 15). Of particular interest was thegeneral use of this methodology to allow synthesis of versatile ketone62 by formation of the C1-C2 bond from thioester 60 and organostannane61 (X═O or NR). Condensative cyclization of the urea or guanidinefunction of intermediate 62 on to the C1-carbonyl would provide anexpeditious route to the corresponding imidazol-2-one (X═O) or relatedazaheterocycle 63, common substructures in various natural products.

In some embodiments, C₆H₄-p-Me is replaced with another suitable organicgroup, for example, R⁹.

A provided cross-coupling reaction was effective for both alkyl and arylthioester coupling partners. Both cyclohexanecarbonyl thioester 64 andbenzoyl thioester 65 underwent efficient cross-coupling with stannyltriazone 47 to give the corresponding ketones 71 and 72 in 95% and 99%yield, respectively (Table 2, entries 1 and 2). Consistent with datapresented in Table 1, the use of organostannane 46, containing n-butylauxiliary ligands, as a coupling partner resulted in relatively low butgood yield (Table 2, entry 3) due to competitive formation of theundesired n-butyl ketone byproduct. Stannyl guanidine 67 proved to behighly effective for the introduction of the guanidine functionality asillustrated through its cross-coupling with thioesters 65 and 66,affording the corresponding ketones 73 and 75, respectively (Table 2,entries 4 and 6). Importantly, ketones 73 and 75 could be readilyconverted to the corresponding 2-aminoimidazoles in quantitative yieldupon treatment with TFA and warming, highlighting the synthetic utilityof the method as a means to generate 2-aminoimidazoles (Table 2, entries5 and 7). Stannyl triazone 68 was found to undergo smooth coupling withadipic thioester 66 to provide diketone 77 in 82% yield (Table 2, entry8). Under provided standard reaction condition, the stannyl urea 69 wasfound to afford the desired cross-coupling with the complex thioester(+)-45 to give the corresponding ketone, which after treatment withmethanolic hydrogen chloride at 65° C. provided(+)-O-methyl-pre-agelastatin A (39, 58% yield and 99% ee, Table 2, entry9). This direct coupling between thioester (+)-45 and stannyl urea 69enabled us to further streamline the synthesis of (−)-agelastatin A (1)to seven steps from commercially available material. Similarly,(+)-O-methyl-pre-agelastatin D (53 Table 2, entry 10) could be preparedfrom thioester (+)-45 and urea 70 in 62% yield (2 steps), which enabledthe first synthetic access to (−)-agelastatin D (4, vide supra). Theefficient union of a variety of aminostannanes and thioester fragmentsand subsequent direct conversion of the keto-triazone and keto-guanidineintermediates to the corresponding imidazolones and aminoimidazolesshowed that provided methods could be used for the synthesis of othercompounds, for example, coroidin based natural products such ascyclooroidin (11), nagelamides, sceptrins, and many other derivatives.

TABLE 2 Copper-mediated thioester-aminostannane cross-coupling andapplication to azaheterocycle synthesis.

stannane CuTc yield entry thioester (equiv) equiv product (%) 1

1.2

95 2

47 (1.5) 1.2

99 3 65

1.5 72 52 4 65

1.0

96 5 65 67 (1.1) 1.0

96^(a) 6

67 (3.0) 2

>99 7 66 67 (3.0) 2

>99^(b) 8 66

2.3

82

9 (+)-45 69 R = Me (3) 2.5 (+)—O—Me—Pre-agelastatin A 58^(c) (39), R =Me 10 (+)-45 70 R = H (3) 2 (+)—O—Me—Pre-agelastatin D 62^(d) (53), R =H a. The ketone intermediate 73 was treated with TFA in toluene at 85°C.; yield over two steps. b. The ketone intermediate 75 was treated withTFA in toluene at 70° C.; yield over two steps. c. ketone intermediatewas filtered and treated with HCl in methanol at 65° C.; one step. d.Cross-coupling intermediate was isolated and treated with HCl inmethanol at 45° C.; yield over two steps. Tol = C₆H₄—p—Me, c-Hex =cyclohexyl.

Anticancer Activity

The six (−)-agelastatin alkaloids (1-6) as well as eightstructurally-related alkaloids and advanced intermediates were tested asexamples for anti-cancer activity. The activities against five humancell lines were first measured. Random reports have tested the activityof (−)-agelastatin A (1), however, it was unknown before for whatcancer(s), if any, agelastatin alkaloids could be used for treatment.

TABLE 3 Assessment of the anti-cancer activity of (−)-agelastatins A-Fand advanced intermediates against human cell lines. ^(a) Cmpd U-937(μM) HeLa (μM) A549 (μM) BT549 (μM) IMR90 (μM) (−)-1  0.067 ± 0.0030.708 ± 0.090 1.05 ± 0.14 0.278 ± 0.076 1.11 ± 0.35 (−)-2  1.06 ± 0.164.8 ± 1.2 >10 4.8 ± 1.1 >10 (−)-3  >10 >10 >10 >10 >10 (−)-4  0.240 ±0.033 1.00 ± 0.20 0.92 ± 0.16 0.631 ± 0.082 2.75 ± 0.60 (−)-5  2.56 ±0.13 8.60 ± 0.81 >10 6.9 ± 2.5 >10 (−)-6  >10 >10 >10 >10 >10(−)-50 >10 >10 >10 >10 >10 (−)-51 >10 >10 >10 >10 >10(−)-52 >10 >10 >10 >10 >10 (+)-39 >10 >10 >10 >10 >10(+)-44 >10 >10 >10 >10 >10 (+)-45 >10 >10 >10 >10 >10(+)-48 >10 >10 >10 >10 >10 (+)-53 >10 >10 >10 >10 >10 ^(a) Cell lines:U-937, lymphoma; HeLa, cervical carcinoma; A549, non-small cell lungcarcinoma; BT549, breast carcinoma; IMR90, immortalized lungfibroblasts; 48-hour IC₅₀ values (in μM) as determined by MTS (U-937)and SRB (HeLa, A549, BT549, and IMR90); MTS =3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium);SRB = sulforhodamine B.

Six (−)-agelastatins along with eight closely related derivativesprepared in the above examples were tested (Table 3). The six(−)-agelastatin alkaloids (1-6, respectively),(−)-O-methyl-di-epi-agelastatin A (50), (−)-dehydroagelastatin A (51),(−)-di-epi-agelastatin C (52), (+)-O-methyl-pre-agelastatin A and D (39and 53, respectively), along with bicyclic pyrroles (+)-44, (+)-45, andtriazone (+)-48 were tested for their ability to induce cell death infour human cancer cell lines (U-937, lymphoma; HeLa, cervical carcinoma;A549, non-small cell lung carcinoma; and BT549, breast carcinoma) andone immortalized normal human cell line (IMR90, lung fibroblasts) aftera 48-hour exposure. As shown in Table 3, (−)-agelastatin A (1) exhibitedthe highest potency in all cell lines tested, whereas (−)-agelastatins C(3) and F (6) showed little activity at the concentrations examined.Furthermore, enhanced activities in U-937 (20×) cell relative to theother cell lines (Table 3) were observed. (−)-Agelastatin B (2) and(−)-agelastatin E (5) showed relatively weaker activity, albeit with thesame overall pattern as alkaloids (−)-1 and (−)-4. None of theepi-agelastatin derivatives [(−)-50 or (−)-52],O-methyl-pre-agelastatins [(+)-39 or (+)-53], dehydroagelastatin (−)-51or any of structurally simpler derivatives [(+)-44, (+)-45, or (+)-48]showed any activity at the concentrations tested against these celllines (Table 3).

This set of data allows the first direct comparison of agelastatinalkaloids and suggest that, without the intention to be limited bytheory, the stereochemistry for the imidazolidinone ring is crucial[compare (−)-5 vs. (−)-50]. Not wishing to be bound by theory,Applicants note that addition of the C14-bromide substituent to thepyrrole, in some embodiments, is detrimental to activity (5-20 foldreduction) of the agelastatins [compare (−)-1 vs. (−)-2, and (−)-4 vs.(−)-6]; and demethylation of the imidazolidinone ring gives more modestreductions (1-5 fold reductions) in anticancer potency as seen bycomparing (−)-agelastatin A (1) and (−)-agelastatin D (4). In someembodiments, methylation of the C5-hydroxyl reduces the activity by >10fold as evident by comparing (−)-agelastatin A (1) and (−)-agelastatin E(5). In some embodiments, C4-hydroxylation abolishes activity asdemonstrated by comparing (−)-agelastatin A (1) and (−)-agelastatin C(3).

Anticancer Activity in Blood Cancer Cells

Based on the surprising and exceptional potency of (−)-agelastatins A(1) and D (4) against U-937 cells relative to the other cell linestested, five additional blood cancer cell lines were tested for theirsensitivity to the agelastatin alkaloids. These cell lines spanned avariety of cancer types (CEM, acute lymphoblastic leukemia; Jurkat,acute T-cell leukemia; Daudi, Burkitt's lymphoma; HL-60, acutepromyelocytic leukemia; CA46, Burkitt's lymphoma). After a 48-hourincubation, the ability of (−)-agelastatins A-F (1-6) to induce celldeath was evaluated. As shown in Table 4, all five cell lines showedremarkable sensitivity to (−)-agelastatin A (1). The same trends inpotency observed for the various agelastatins with the general cellpanel (Table 3) were also observed. These results highlight thatcompounds of formula I are unexpectedly potent against blood cancers.

TABLE 4 48-hour activity of (−)-agelastatins A-F against human bloodcancer cell lines. ^(a) Cmpd CEM (μM) Jurkat (μM) Daudi (μM) HL-60 (μM)CA46 (μM) (−)-1 0.020 ± 0.002 0.074 ± 0.007 0.020 ± 0.003 0.138 ± 0.0660.187 ± 0.071 (−)-2 0.29 ± 0.20 0.75 ± 0.44 0.46 ± 0.28 2.4 ± 1.0 1.07 ±0.42 (−)-3 2.1 ± 1.3 5.31 ± 0.35 7.2 ± 2.9 >10 >10 (−)-4 0.074 ± 0.0250.210 ± 0.063 0.202 ± 0.015 0.54 ± 0.12 0.46 ± 0.24 (−)-5 0.83 ± 0.371.50 ± 0.33 1.41 ± 0.53 4.6 ± 3.6 2.45 ± 0.95 (−)-6 >10 >10 >10 >10 >10^(a) Cell lines: CEM, acute lymphoblastic leukemia; Jurkat, acute T-cellleukemia; Daudi, Burkitt's lymphoma; HL-60, acute promyelocyticleukemia; CA46, Burkitt's lymphoma; 48-hour IC₅₀ values (in μM) asdetermined by MTS; MTS =3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium).

Hemolytic Activity

It was surprisingly found that compounds in the provided compositionsand methods are not only unexpectedly potent toward blood cancer cells,but also have surprisingly low hemolytic activity. All fourteencompounds in Table 3 were evaluated for their hemolytic activity (FIG.1). Notably, none of agelastatins (−)-1, (−)-2, (−)-4, or (−)-5 show anynonspecific hemolysis of red blood cells. Together with the exceptionalpotency of these compound, for example, (−)-agelastatin A (1), against arange of blood cancer cell lines, this high degree of selectivity makesthese compounds valuable treatment for blood cancers.

Apoptotic Activity

Compounds of formula I, such as (−)-agelastatins A (1) and D (4) induceapoptotic cell death. Procaspase-3 maturation and PARP-1 cleavage werereadily detected via Western blotting, and phosphatidyl serine exposureis detected by antibody staining and flow cytometry. As shown in FIG. 2,(−)-agelastatins A (1) and D (4) induced dose-dependent activation ofprocaspase-3 to active caspase-3, and cleavage of PARP-1, consistentwith apoptosis.

It was next examined whether (−)-agelastatins A (1) and D (4) inducedphosphatidylserine exposure prior to membrane permeabilization. This wasdetermined by evaluating the timing of FITC-labeled annexin-V to thephosphatidylserines relative to the incorporation of propidium iodide, aDNA stain that can only enter dead cells. As shown by the scatterplotsin FIG. 3, the number of apoptotic cells (lower right quadrant in FIG.3) increases with dose of compound. These results show, for the firsttime, that these compounds induce apoptotic death of cancer cells.

Cell Cycle Arrest

Compounds of the provided compositions and methods induce cell cyclearrest. As shown in FIG. 5, provided compounds induced arrest in theG2/M phase. While arrest in the G2/M phase is commonly associated withdisruption of microtubules within the cell, using confocal microscopy,it is determined that neither (−)-agelastatin A (1) nor (−)-agelastatinD (4) affects tubulin dynamics within cells.

An exemplary concise, stereocontrolled, and biosynthetically inspiredsynthetic strategy toward the agelastatin alkaloids, the development aversatile new synthetic methodology for azaheterocycle synthesis, andits successful implementation to the synthesis of all known(−)-agelastatins (1-6) and many derivatives were described. Key featuresof the exemplary syntheses include: 1) the early introduction ofC13-bromide to suppress C7-enolization, 2) the development of aCuTC-mediated cross-coupling reaction between thioester andorganostannane, 3) a new [4+1] annulation approach for the synthesis ofimidazolones and related azaheterocycles, and 4) the validation of thebioinspired use of the imidazolone for an advanced stage C-ringformation, C4-C8 bond formation and introduction of three stereogeniccenters. The efficiency of the provided synthetic sequence washighlighted by >1 gram batch preparation of (−)-agelastatin A (1). Thegenerality of the provided synthesis allowed for the first side-by-sidetesting of all known agelastatin alkaloids for their ability to inducecell death in U-937 (lymphoma), HeLa, (cervical carcinoma), A549(non-small cell lung carcinoma), BT549 (breast carcinoma), and IMR90(immortalized lung fibroblasts) human cell lines. Provided compounds,such as (−)-Agelastatin A (1), exhibited the high potency toward bloodcancer cells. Provided data show, for the first time, that compounds inprovided compositions and methods, such as (−)-agelastatins A and D,induce apoptotic death of cancer cells and may not affect tubulindynamics within cells. Applicants also show that these molecules mayarrest cell growth in the G2/M phase. The present invention provides newmethods and compositions for treating blood cancers; compounds ofprovided methods, such as (−)-agelastatins A (1), are highly potentagainst blood cancer cells (20-190 nM) without affecting normal redblood cells (>333 μM).

Details for all biological assays as well as experimental procedureswere described below. For crystal structure of S25 (CIF): CCDC 955147.

Materials. Commercial reagents and solvents were used as received withthe following exceptions: dichloromethane, diethyl ether,tetrahydrofuran, acetonitrile, toluene, methanol, triethylamine, andpyridine were purchased from J.T. Baker (Cycletainer™) and were purifiedby the method of Grubbs et al. under positive argon pressure. Copperthiophene 2-carboxylate (CuTC), a tan colored solid, was purchased fromMatrix Inc. and was used as received. The molarity of sec-butyllithiumsolutions were determined by titration using diphenylacetic acid as anindicator (average of three determinations).

Instrumentation. Proton (¹H) and carbon (¹³C) nuclear magnetic resonancespectra were recorded with Varian inverse probe 500 INOVA, Varian 500INOVA, and Bruker AVANCE-400 NMR spectrometers. Proton nuclear magneticresonance (¹H NMR) spectra are reported in parts per million on the δscale and are referenced from the residual protium in the NMR solvent(CDCl₃: δ 7.24 (CHCl₃), CD₃OD: δ 3.31 (CHD₂OD). Data is reported asfollows: chemical shift [multiplicity (s=singlet, d=doublet, t=triplet,q=quartet, st=sextet, sp=septet, m=multiplet, app=apparent, br=broad),coupling constant(s) in Hertz, integration, assignment. Carbon-13nuclear magnetic resonance (¹³C NMR) spectra are reported in parts permillion on the δ scale and are referenced from the carbon resonances ofthe solvent (CDCl₃: δ 77.23, CD₃OD: δ 49.15). Data is reported asfollows: chemical shift. Infrared data (IR) were obtained with aPerkin-Elmer 2000 FTIR and are reported as follows: [frequency ofabsorption (cm⁻¹), intensity of absorption (s=strong, m=medium, w=weak,br=broad)]. High-resolution mass spectrometric data (HRMS) were recordedon a Bruker APEXIV 4.7 t FT-ICR-MS spectrometer using electrosprayionization (ESI) source or direct analysis in real time (DART)ionization source.

Positional Numbering System. In assigning the ¹H and ¹³C NMR data of allintermediates en route to the stotal synthesis of (−)-1 through (−)-6Applicants have employed a uniform numbering system consistent with thatof the final targets.

Information for Key Compounds. For complete experimental procedures andfull characterization data for all (−)-agelastatin alkaloids A-F (1-6,respectively) in addition to the eight advanced derivatives (+)-39,(+)-44, (±)-48, (−)-50, (−)-51, (−)-52, and (+)-53 examined in theanticancer activity assays, please see the supporting information of M.Movassaghi, D. S. Siegel, S. Han, Chem. Sci., 2010, 1, 561, which ishereby incorporated by reference. For complete experimental proceduresand full characterization data for the key compounds (+)-41, 47, (−)-54,55, and (±)-56 discussed in the optimized route, please see thesupporting information of M. Movassaghi, D. S. Siegel, S. Han, Chem.Sci., 2010, 1, 561. Complete experimental procedures and fullcharacterization data for all new substrates and products reported inTable 3 were described herein.

After completing the first generation total synthesis of (±)-agelastatinA (1) using N—OMe substituted amide derivative (±)-34 (Scheme 8),Applicant could further streamline the synthesis by using lactam (±)-S3(Scheme S1). Imide (±)-S2 was obtained in a single step from pyrrole(+)-S1 upon treatment with chlorosulfonylisocyanate followed byhydrolysis and in situ cyclization (83% yield). Imide (±)-S2 wasconverted to methyl ester (±)-S3 by reduction with sodium borohydride inmethanol followed by addition of p-toluenesulfonic acid hydrate in onestep (89% yield). Tin-lithium exchange of organostannane 46 and directaddition to methyl ester (±)-S3 gave the keto-triazone (±)-S4 in 80%yield. Treatment of ketone (±)-S4 with2,4,4,6-tetrabromocyclohexa-2,5-dienone (TABCO) in ethanol at −20° C.provided C13-bromo ketone (±)-48 in 63% yield. Solvolysis of triazone(±)-48 in methanolic hydrogen chloride solution at 45° C. provided(±)-O-methyl-pre-agelastatin A (39, 49% yield). Following the conditionsdescribed in the text of this manuscript (Scheme 8),(±)-O-methyl-pre-agelastatin A (39) was converted to (±)-agelastatin A(1) and (±)-di-epi-agelastatin A (40).

Conditions: (a) LiBH₄, THF, 23° C., 96%; (b) DMP, CH₂Cl₂, 0° C., 80%;(c) n-BuLi, THF, −78° C.; CeCl₃, THF, −78→−45° C., 64%; (d) IBX, DMSO,23° C., 93%.

Our first synthetic access to enantiomerically enriched (−)-agelastatinA (1) was realized via addition of organocerium triazone derivetive tobrominated bicyclic aldehyde S6 (Scheme S2). Methyl ester (+)-44 wasreduced to alcohol S5 in the presence of lithium borohydride in THF in96% yield (Scheme S2). The resulting alcohol S5 was oxidized to aldehydeS6 upon treatment with Dess-Martin periodinane in 80% yield. For theaddition of metallated triazone to aldehyde S6, organocerium basedtriazone reagent was most effective, resulting in the secondary alcoholsS7 in 64% yield as a mixture of diastereomers. Alcohol S7 was oxidizedto keto triazone (+)-48 in the presence of IBX in DMSO at 23° C. in 93%yield and 99% ee. Keto triazone (+)-48 could be further converted to(−)-agelastatin A (1, 99% ee, Scheme 11).

Pyrrole H-S1 was treated with chlorosulfonyl isocyanate followed byreductive quenching with tributylphosphine to provide amide (+)-S8 in59% yield and 99% ee (Scheme S3). Treatment of amide (+)-S8 with 2.3equivalent of 2,4,4,6-tetrabromo-2,5-cyclohexadienone affordeddibrominated amide H-S9 in 79% yield and 99% ee. Treatment of amide(+)-S9 with sodium borohydride in methanol followed by addition ofp-toluenesulfonic acid hydrate gave methyl ester (±)-S10. Methyl ester(+)-S10 could be reduced to alcohol S11 in the presence of lithiumborohydride in tetrahydrofuran solution in 94% yield. The resultingalcohol S11 was oxidized to aldehyde S12 upon treatment with Dess-Martinperiodinane in 83% yield. For the addition of metallated triazone toaldehyde S12, organocerium reagent was most effective to give thesecondary alcohols S13 in 73% yield. The resulting secondary alcohol S13was oxidized to keto triazone (+)-S14 in the presence of IBX in DMSO at23° C. in 90% yield. Solvolysis of triazone moiety in ketone (±)-S14 andcondensative cyclization in methanolic hydrogen chloride at 45° C.provided (+)-O-methyl-pre-agelastatin B (S15, 61% yield). For the finalstep of the initial total synthesis of (−)-agelastatin B (2), exposureof imidazolones (+)-S15 in aqueous media containing TFA at 95° C.afforded the desired natural product (−)-agelastatin B (2, 99% ee) alongwith (−)-di-epi-agelastatin B (S16) in 58% yield (2:1, 2:S16).

Influence of the C13-Substituent on the Conformation of the C7-H

The minimized energy conformation of imide S17 and C13-brominated imideS18 showed a difference in their H7-C7-C8-O8 dihedral angles. While theH7-C7-C8-O8 dihedral angle of imide S17 was calculated to be 76°, thatof C13-brominated imide S18 was calculated to be 56° (FIG. 5). Withoutthe intention to be bound by theory, the smaller dihedral angle of imideS18 can be rationalized based on the allylic strain between theC13-bromine and C6-methylene, which forces the alkyl group at C7 toadopt a conformation almost orthangonal with respect to the B-ring.

The H7-C7-C8-H8 dihedral angle of acyliminium ion S19 was calculated tobe 53°, while that of C13 brominated acyliminium ion 8 was calculated tobe 31° (Figure S2). Thus the C7 proton of acyliminium ion 8 would beless prone to deprotonation as the overlap of C7-H7 σ orbital to C8-N9π* orbital would be less than that of acyliminium ion S19.

Rate of C4-Deuterium Incorporation in (+)-O-Methyl-Pre-Agelastatins A(39) and D (53)

(+)-O-methyl-pre-agelastatin A (39, 4.0 mg, 11 μmol, 1 equiv) and(+)-O-methyl-pre-agelastatin D (53, 4.0 mg, 11 μmol, 1 equiv) wereseparately dissolved in methanol-d₄ (0.78 mL) and the ¹H NMR spectrawere recorded at 23° C. for the reference at t=0. The hydrogen-deuteriumexchange experiment was initiated by adding methanesulfonic acid (15 μL,0.23 mmol, 21 equiv) into the samples. The ¹H NMR spectra were thenrecorded at appropriate time intervals, and the amount of deuteriumincorporation at C4 was recorded. (First order kinetics to the substratewas assumed. Hence −d[A]/dt=k[A], where [A] is the substrateconcentration).

TABLE 5 Deuterium incorporation at C4 of (+)-O-methyl-pre-agelastatins A(39) and D (53). Time (h) 0 0.1 0.5 0.8 2.0 4.0 13.5 18.0 20.5 26.0d-incoporation 0 5.0 10.3 11.4 22.6 40.1 80.0 86.6 91.0 94.3 at C4 of 39(%) d-incorporation 0 0 0 1.5 3.3 6.1 14.6 16.9 19.7 25.7 at C4 of 53(%) [39] (mol/L) 0.0141 0.0134 0.0126 0.0125 0.011 0.0084 0.0028 0.00190.0012 0.0008 [53] (mol/L) 0.0141 0.0141 0.0141 0.013889 0.01363 0.01320.0120 0.0117 0.0113 0.0104 ln[39] −4.2615 −4.3128 −4.3702 −4.3826−4.5177 −4.7740 −5.8710 −6.2714 −6.6695 −7.1262 ln[53] −4.2615 −4.2616−4.262 −4.277 −4.3 −4.325 −4.4194 −4.447 −4.4809 −4.5586

S,S-Di-p-tolyl hexanebis(thioate) 66: To a flask charged with adipicacid (S20, 4.0 g, 27 mmol, 1 equiv) was added thionyl chloride (5.0 mL,68 mmol, 2.5 equiv) and the reaction flask was equipped with a refluxcondensor and heated to 85° C. (The exhaust gases were passed through a5 N aqueous potassium hydroxide solution). After 1.5 h, the reactionmixture was allowed to cool to 23° C. and concentrated under reducedpressure to afford acyl chloride S21 as a viscous oil. The resultingcrude material was dissolved in dichloromethane (10 mL) and theresulting mixture was transferred to a solution of 4-methyl-benzenethiol(7.3 g, 57 mmol, 2.1 equiv) in dichloromethane (30 mL) via cannula at 0°C. The reaction mixture was allowed to gently warm to 23° C. After 2 h,triethylamine (2.0 mL, 14 mmol, 0.52 equiv) was added to the reactionmixture. After 25 min, more triethylamine (3.0 mL, 22 mmol, 0.79 equiv)was added to the reaction mixture. After 16.5 h, the reaction mixturewas diluted with dichloromethane (210 mL) and saturated aqueous sodiumbicarbonate solution (250 mL) and the layers were separated. The aqueouslayer was extracted with dichloromethane (250 mL), and the combinedorganic layers were dried over anhydrous sodium sulfate, were filtered,and were concentrated under reduced pressure. The residue was purifiedby flash column chromatography (silica gel: diam. 9.0 cm, ht. 12 cm;eluent: 11% ethyl acetate in hexanes) to afford thioester 66 (4.6 g,47%) as a white solid. ¹H NMR (500 MHz, CDCl₃, 21° C.): δ 7.27 (app-d,J=8.1 Hz, 4H), 7.20 (app-d, J=7.9 Hz, 4H), 2.67-2.64 (m, 4H), 2.36 (s,6H), 1.78-1.75 (m, 4H). ¹³C NMR (125.8 MHz, CDCl₃, 21° C.): δ 197.7,139.9, 134.6, 130.2, 124.3, 43.2, 25.0, 21.5. FTIR (neat) cm⁻¹: 2929(m), 1687 (s), 1493 (m), 1034 (m), 813 (s). HRMS (ESI) (m/z): calc'd forC₂₀H₂₂NaO₂S2, [M+Na]⁺: 381.0959, found: 381.0965. TLC (17% ethyl acetatein hexanes), Rf: 0.53 (CAM, UV).

1-((Tricyclohexylstannyl)methyl)-N,N′-di-tert-butylcarbamoylguanidine(67): Stannylamine S22 (910 mg, 2.28 mmol, 1 equiv) was dissolved inacetonitrile (60 mL), and(E)-tert-butyl(((tert-butoxycarbonyl)imino)(1H-pyrazol-1-yl)methyl)carbamate(S23, 1.09 g, 3.43 mmol, 1.50 equiv) was added sequentially at 23° C.After 11 h, the resulting mixture was concentrated under reducedpressure, and the crude residue, adsorbed onto silica gel, was purifiedby flash column chromatography (silica gel: diam. 4.0 cm, ht. 12 cm;eluent: 3.3% ethyl acetate in hexanes) to afford tricyclohexyltinreagent 67 (1.3 g, 91%) as a white solid. ¹H NMR (500 MHz, CDCl₃, 21°C.): δ 11.39 (s, 1H), 8.44 (t, J=5.1 Hz, 1H), 3.08 (d, J=5.6 Hz, 2H),1.84 (t, J=4.4 Hz, 6H), 1.62 (d, J=9.6 Hz, 9H), 1.53 (t, J=7.1 Hz, 9H),1.48 (s, 9H), 1.45 (s, 9H), 1.28-1.21 (m, 9H). ¹³C NMR (125.8 MHz,CDCl₃, 21° C.): δ 163.9, 155.8, 153.6, 82.9, 78.9, 32.4, 29.5, 28.6,28.2, 27.5, 27.4, 24.1. FTIR (neat) cm⁻¹: 3327 (s), 2917 (s), 2846 (s),1717 (s), 1642 (s), 1575 (s), 1409 (s), 1337 (s), 1157 (s), 1052 (s),909 (m), 735 (m). HRMS (ESI) (m/z): calc'd for C₃₀H₅₆N₃O₄Sn, [M+H]⁺:642.3293,found: 642.3290. TLC (10% ethyl acetate in hexanes), Rf: 0.56(CAM).

5-Benzyl-1-methyl-3-((tricyclohexylstannyl)methyl)-1,3,5-triazinan-2-one(68): To a solution of triazone S24 (1.5 g, 6.8 mmol, 2.0 equiv) intetrahydrofuran (40 mL) at −78° C. was added sec-butyllithium (1.4 M incyclohexane, 4.9 mL, 6.8 mmol, 2.0 equiv) via syringe to result in anorange homogeneous solution. After 5 min, a solution of tricyclohexyltinchloride (1.42 g, 3.42 mmol, 1 equiv) in tetrahydrofuran (10 mL) at −78°C. was transferred to the resulting bright orange mixture via cannulaover a 3 min period. After 8 min, saturated aqueous ammonium chloridesolution (5 mL) was added via syringe. The resulting mixture waspartitioned between dichloromethane (250 mL) and water (200 mL). Thelayers were separated, the aqueous layer was extracted withdichloromethane (250 mL), and the combined organic layers were driedover anhydrous sodium sulfate, were filtered, and were concentratedunder reduced pressure. The crude residue was purified by flash columnchromatography (silica gel: diam. 5 cm, ht. 10 cm; eluent: hexanes then17% ethyl acetate in hexanes) to afford stannyltriazone 68 (1.8 g, 90%)as a white solid. ¹H NMR (500 MHz, CDCl₃, 21° C.): δ 7.34-7.24 (m, 5H),4.10 (s, 2H), 4.03 (s, 2H), 3.90 (s, 2H), 2.81 (s, 3H), 2.75 (s, 2H),1.84 (dd, J=12.5, 2.0 Hz, 3H), 1.63 (d, J=8.9 Hz, 12H), 1.55-1.39 (m,6H), 1.31-1.17 (m, 12H). ¹³C NMR (125.8 MHz, CDCl₃, 21° C.): δ 156.1,137.9, 129.1, 128.7, 127.7, 69.7, 67.6, 55.8, 32.9, 32.4, 29.5, 29.0,27.9, 27.4. FTIR (neat) cm⁻¹: 2917 (s), 2229 (m), 1634 (s), 1519 (s),1445 (s), 1408 (m), 1297 (s), 1144 (m), 908 (s), 735 (s). HRMS (ESI)(m/z): calc'd for C₃₀H₅₀N₃OSn, [M+H]⁺: 588.2987, found: 588.2976. TLC(17% ethyl acetate in hexanes), Rf: 0.32 (CAM, UV).

1-(2-Cyclohexyl-2-oxoethyl)-3-methyl-5-(p-tolyl)-1,3,5-triazinan-2-one(71): Anhydrous tetrahydrofuran (1.0 mL, degassed thoroughly by passageof a stream of argon) was added via syringe to a flask charged withthioester 64 (12.0 mg, 51.2 μmol, 1 equiv), triazone 47 (36.0 mg, 61.4μmol, 1.20 equiv), and copper(I)-thiophene-2-carboxylate (CuTC, 15.3 mg,76.8 μmol, 1.50 equiv) at 23° C. under an argon atmosphere, and thereaction mixture was heated to 50° C. After 1 h, the reaction mixturewas allowed to cool to 23° C. and was filtered through a plug of celitewith ethyl acetate washings (3×1 mL). The resulting mixture waspartitioned between ethyl acetate (20 mL) and saturated ammoniumchloride aqueous solution (20 mL). The aqueous layer was extracted withethyl acetate (2×20 mL), and the combined organic layers were dried overanhydrous sodium sulfate, and were concentrated under reduced pressure.The crude residue was purified by flash column chromatography (silicagel: diam. 2 cm, ht. 10 cm; eluent: 25% ethyl acetate in hexanes) toafford ketotriazone 71 (16 mg, 95%) as a colorless oil. ¹H NMR (500 MHz,CDCl₃, 21° C.): δ 7.08 (d, J=8.0 Hz, 2H), 6.94 (d, J=8.6 Hz, 2H), 4.69(s, 2H), 4.66 (s, 2H), 4.09 (s, 2H), 2.88 (s, 3H), 2.32 (tt, J=11.4, 3.4Hz, 1H), 2.27 (s, 3H), 1.80 (dd, J=13.3, 2.2 Hz, 2H), 1.76-1.72 (m, 2H),1.66-1.60 (m, 2H), 1.32 (ddd, J=15.2, 12.4, 3.1 Hz, 2H), 1.25-1.15 (m,2H). ¹³C NMR (125.8 MHz, CDCl₃, 21° C.): δ 210.4, 156.1, 146.0, 132.6,130.1, 119.8, 67.4, 67.4, 53.5, 48.2, 32.4, 28.4, 25.9, 25.7, 20.8. FTIR(neat) cm⁻¹: 2929 (s), 2855 (m), 1720 (m), 1647 (s), 1514 (s), 1300 (m),1198 (m), 829 (m). HRMS (ESI) (m/z): calc'd for C₁₉H₂₆N₃O₂, [M−H]⁻:328.2025, found: 328.2030. TLC (ethyl acetate), Rf: 0.40 (CAM).

1-Methyl-3-(2-oxo-2-phenylethyl)-5-(p-tolyl)-1,3,5-triazinan-2-one (72):Anhydrous tetrahydrofuran (1.1 mL, degassed thoroughly by passage of astream of argon) was added via syringe to a flask charged with thioester65 (12.0 mg, 52.6 μmol, 1 equiv), triazone 47 (37.0 mg, 63.1 μmol, 1.20equiv), and copper(I)-thiophene-2-carboxylate (CuTC, 15.7 mg, 78.8 μmol,1.50 equiv) at 23° C. under an argon atmosphere, and the reactionmixture was heated to 50° C. After 1 h, the reaction mixture was allowedto cool to 23° C. and was filtered through a plug of celite with ethylacetate washings (3×1 mL). The resulting mixture was partitioned betweenethyl acetate (20 mL) and saturated ammonium chloride aqueous solution(20 mL). The aqueous layer was extracted with ethyl acetate (2×20 mL),and the combined organic layers were dried over anhydrous sodiumsulfate, were filtered, and were concentrated under reduced pressure.The crude residue was purified by flash column chromatography (silicagel: diam. 2 cm, ht. 10 cm; eluent: 25% ethyl acetate in hexanes) toafford ketotriazone 72 (17 mg, 99%) as a colorless oil. ¹H NMR (500 MHz,CDCl₃, 21° C.): δ 7.92 (dd, J=8.4, 1.2 Hz, 2H), 7.55 (tt, J=7.4, 1.2 Hz,1H), 7.42 (app-t, J=7.8 Hz, 2H), 7.07 (d, J=8.0 Hz, 2H), 6.95 (app-d,J=8.5 Hz, 2H), 4.80 (s, 2H), 4.73 (s, 2H), 4.72 (s, 2H), 2.92 (s, 3H),2.28 (s, 3H). ¹³C NMR (125.8 MHz, CDCl₃, 21° C.): δ 196.1, 156.1, 145.9,135.2, 133.8, 132.6, 130.1, 128.9, 128.3, 119.8, 67.4, 67.3, 52.5, 32.5,20.3. FTIR (neat) cm⁻¹: 2888 (m), 1694 (m), 1638 (s), 1513 (s), 1288(m), 1219 (m), 750 (m). HRMS (ESI) (m/z): calc'd for C₁₉H₂₀N₃O₂, [M−H]⁻:322.1556, found: 322.1562. TLC (ethyl acetate), Rf: 0.46 (CAM, UV).

(E)-1,2-Diboc-3-(2-oxo-2-phenylethyl)guanidine (73): Anhydroustetrahydrofuran (6.0 mL, degassed thoroughly by passage of a stream ofargon) was added via syringe to a flask charged with thioester 65 (36.6mg, 0.160 mmol, 1 equiv), stannylguanidine 67 (113 mg, 0.176 mmol, 1.10equiv), and copper(I)-thiophene-2-carboxylate (CuTC, 32.8 mg, 0.165mmol, 1.03 equiv) at 23° C. under an argon atmosphere, and the reactionmixture was heated to 50° C. After 1 h, the reaction mixture was allowedto cool to 23° C., and 5% ammonium hydroxide aqueous solution (15 mL)was added to the reaction mixture. The resulting mixture was extractedwith dichloromethane (2×15 mL), and the combined organic layers weredried over anhydrous sodium sulfate, were filtered, and wereconcentrated under reduced pressure. The crude residue was purified byflash column chromatography (silica gel: diam. 2.5 cm, ht. 15 cm;eluent: 11% ethyl acetate in hexanes) to afford ketoguanidine 73 (58 mg,96%). ¹H NMR (500 MHz, CDCl₃, 21° C.): δ 11.5 (s, 1H, NH), 9.41 (s, 1H,NH), 7.98 (dd, J=8.5, 1.2 Hz, 2H), 7.59 (tt, J=7.4, 1.3 Hz, 1H), 7.46(app-t, J=7.7 Hz, 1H), 4.92 (d, J=4.1 Hz, 2H), 1.51 (s, 9H), 1.50 (s,9H). ¹³C NMR (125.8 MHz, CDCl₃, 21° C.): δ 193.4, 163.5, 156.1, 153.1,134.4, 134.3, 129.1, 128.3, 83.5, 79.8, 48.4, 28.4, 28.3. FTIR (neat)cm⁻¹: 3319 (m), 2980 (m), 1727 (s), 1697 (m), 1642 (s), 1618 (s), 1409(m), 1308 (s), 1148 (s), 734 (m). HRMS (ESI) (m/z): calc'd forC₁₉H₂₈N₃O₅, [M+H]⁺: 378.2029, found: 378.2035. TLC (20% ethyl acetate inhexanes), Rf: 0.44 (CAM, UV).

2-Amino-5-phenyl-1H-imidazol-3-ium 2,2,2-trifluoroacetate (74): To aflask charged with ketoguanidine 73 (57.9 mg, 0.153 mmol, 1 equiv) wasadded toluene (4 mL) and trifluoroacetic acid (120 μL, 1.53 mmol, 10.0equiv) via syringe and the reaction mixture was heated to 85° C. After13.5 h, the reaction mixture was allowed to cool to 23° C. and wasconcentrated under reduced pressure. Water (2 mL) and trifluoroaceticacid (120 μL, 1.53 mmol, 10.0 equiv) were added via syringe to theresidue and the resulting mixture was heated to 85° C. After 1.5 h, thereaction mixture was allowed to cool to 23° C. and was concentratedunder reduced pressure to give 2-aminoimidazole 74 (34 mg, 82%) as apale yellow solid. ¹H NMR (500 MHz, CD₃OD, 21° C.): δ 7.56 (app-d, J=7.2Hz, 2H), 7.43 (app-t, J=7.7 Hz, 2H), 7.34 (app-tt, J=7.4, 1.2 Hz, 1H),7.13 (s, 1H). ¹³C NMR (125.8 MHz, CD₃OD, 21° C.): δ 163.1, 149.7, 130.3,129.7, 129.2, 129.1, 125.6, 109.9, 101.4. FTIR (neat) cm⁻¹: 3182 (br-s),1682 (br-s), 1204 (s), 1139 (s), 842 (m). HRMS (ESI) (m/z): calc'd forC₉H₁₀N₃, [M+H]⁺: 160.0869, found: 160.0867.

(E,E)-1,1′-(2,7-Dioxooctane-1,8-diyl)bis(2′,3-dibocguanidine) (75):Anhydrous tetrahydrofuran (34 mL, degassed thoroughly by passage of astream of argon) was added via syringe to a flask charged with thioester66 (300 mg, 0.836 mmol, 1 equiv), stannylguanidine 67 (1.34 g, 2.09mmol, 2.50 equiv), and copper(I)-thiophene-2-carboxylate (CuTC, 374 mg,1.88 mmol, 2.25 equiv) at 23° C. under an argon atmosphere, and thereaction mixture was heated to 50° C. After 1 h, the reaction mixturewas allowed to cool to 23° C. The resulting mixture was partitionedbetween dichloromethane (145 mL) and 5% ammonium hydroxide aqueoussolution (145 mL). The aqueous layer was extracted with dichloromethane(3×145 mL), and the combined organic layers were dried over anhydroussodium sulfate, were filtered, and were concentrated under reducedpressure. The crude residue was purified by flash column chromatography(silica gel: diam. 4 cm, ht. 10 cm; eluent: 11% ethyl acetate inhexanes) to afford ketoguanidine 75 (549 mg, 100%) as a pale yellowsolid. ¹H NMR (500 MHz, CDCl₃, 21° C.): δ 11.37 (s, 2H), 9.02 (s, 2H),4.28 (d, J=4.3 Hz, 4H), 2.42 (app-s, 4H), 1.60 (t, J=3.1 Hz, 4H), 1.47(s, 9H), 1.46 (s, 9H). ¹³C NMR (125.8 MHz, CDCl₃, 21° C.): δ 203.9,163.4, 155.9, 153.0, 83.5, 79.7, 51.0, 39.9, 28.4, 28.2, 23.1. FTIR(neat) cm⁻¹: 3319 (br-m), 2980 (m), 2253 (w), 1726 (s), 1643 (s), 1618(s), 1408 (m), 1309 (s), 1151 (s), 1058 (m), 734 (m). HRMS (ESI) (m/z):calc'd for C₃₀H₅₃N₆O₁₀, [M+H]⁺: 657.3823, found: 657.3801. TLC (50%ethyl acetate in hexanes), Rf: 0.44 (CAM).

4,4′-(Butane-1,4-diyl)bis(2-amino-1H-imidazol-3-ium)2,2,2-trifluoroacetate (76): Toluene (40 mL) and trifluoroacetic acid(650 μL, 8.36 mmol, 10.0 equiv) were added via syringe to a flaskcharged with ketoguanidine 75 (549 mg, 0.836 mmol, 1 equiv) and theresulting mixture was heated to 75° C. After 16 h, the reaction mixturewas allowed to cool to 23° C. and was concentrated under reducedpressure. Water (20 mL) and trifluoroacetic acid (650 μL, 8.36 mmol,10.0 equiv) were added via syringe to the residue and the resultingmixture was heated to 100° C. After 45 h, the reaction mixture wasallowed to cool to 23° C. and was concentrated under reduced pressure togive 2-aminoimidazole 76 (375 mg, 100%) as a brown solid. ¹H NMR (500MHz, CD₃OD, 21° C.): δ 6.49 (s, 2H), 2.53 (app-t, J=6.5 Hz, 4H), 1.65(app-t, J=7.1 Hz, 4H). ¹³C NMR (125.8 MHz, CD₃OD, 21° C.): δ 162.6,148.8, 128.8, 109.8, 101.4, 28.7, 25.2. FTIR (neat) cm⁻¹: 3179 (br-s),2361 (w), 1702 (s), 1442 (m), 1205 (s), 1134 (s), 845 (m), 723 (m). HRMS(ESI) (m/z): calc'd for C₁₀H₁₇N₆, [M+H]⁺: 221.1509, found: 221.1512.

1,8-Bis(5-benzyl-3-methyl-2-oxo-1,3,5-triazinan-1-yl)octane-2,7-dione(77): Anhydrous tetrahydrofuran (8.0 mL, degassed thoroughly by passageof a stream of argon) was added via syringe to a flask charged withthioester 66 (70.9 mg, 0.198 mmol, 1 equiv), triazone 68 (290 mg, 0.494mmol, 2.50 equiv), and copper(I)-thiophene-2-carboxylate (CuTC, 88.4 mg,0.448 mmol, 2.25 equiv) at 23° C. under an argon atmosphere, and thereaction mixture was heated to 50° C. After 1.5 h, the reaction mixturewas allowed to cool to 23° C. The resulting mixture was partitionedbetween dichloromethane (30 mL) and 5% ammonium hydroxide aqueoussolution (30 mL). The aqueous layer was extracted with dichloromethane(30 mL), and the combined organic layers were dried over anhydroussodium sulfate, were filtered, and were concentrated under reducedpressure. The crude residue was purified by flash column chromatography(silica gel: diam. 3 cm, ht. 11 cm; eluent: 24% chloroform, 5% methanol,and 0.6% ammonium hydroxide in dichloromethane) to afford ketotriazone77 (89 mg, 82%) as a colorless oil. ¹H NMR (500 MHz, CDCl₃, 21° C.): δ7.33-7.26 (m, 10H), 4.19 (s, 4H), 4.15 (s, 4H), 4.00 (s, 4H), 3.99 (s,4H), 2.84 (s, 6H), 2.40 (t, J=6.9 Hz, 4H), 1.57 (q, J=3.3, 4H). ¹³C NMR(100.6 MHz, CDCl₃, 21° C.): δ 206.9, 155.7, 137.8, 129.3, 128.8, 127.8,67.8, 67.5, 55.6, 54.6, 39.6, 32.6, 23.0. FTIR (neat) cm⁻¹: 3442 (br-s),2929 (m), 2237 (w), 1717 (m), 1635 (m), 1506 (m), 1266 (s), 739 (s).HRMS (ESI) (m/z): calc'd for C₃₀H₄₁N₆O₄, [M+H]⁺: 549.3189, found:549.3183. TLC (24% chloroform, 5.4% methanol, and 0.6% ammnoiumhydroxide in dichloromethane), Rf: 0.27 (CAM, UV).

General Reagents and Methods for Biological Assays. For biologicalassays, propidium iodide, phenazine methosulfate, and monoclonalanti-α-tubulin-FITC antibody were purchased from Sigma-Aldrich. The3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazoliumsalt was obtained from Promega. Annexin-V FITC conjugate was purchasedfrom Invitrogen. All Western antibodies were obtained from CellSignaling. Optical densities were recorded on a Spectramax Plus 384(Molecular Devices, Sunnyvale, Calif.). Flow cytometry was performed ona BD Biociences LSR II (San Jose, Calif.) and the data was analyzed asdescribed using FACSDiva software (San Jose, Calif.).

Cell Culture Information. Cells were grown in media supplemented withfetal bovine serum (FBS) and antibiotics (100 μg/mL penicillin and 100U/mL streptomycin). Specifically, experiments were performed using thefollowing cell lines and media compositions: U-937, HeLa, A549, BT549,CEM, Daudi, and Jurkat (RPMI-1640+10% FBS), CA46 (DMEM+10% FBS), HL-60(IMDM+10% FBS), and IMR90 (EMEM+10% FBS). Cells were incubated at 37° C.in a 5% CO₂, 95% humidity atmosphere.

IC₅₀ Value Determination for Adherent Cells using Sulforhodamine B(SRB). Adherent cells (HeLa, A549, BT549, and IMR90) were added into96-well plates (5,000 cells/well for HeLa cell line; 2,000 cells/wellfor A549, BT549, and IMR90 cell lines) in 100 μL media and were allowedto adhere for 2-3 hours. Compounds were solubilized in DMSO as 100×stocks, added directly to the cells (100 μL final volume), and testedover a range of concentrations (1 nM to 10 μM) in triplicate (1% DMSOfinal) on a half-log scale. DMSO and cell-free wells served as the liveand dead control, respectively. After 48 h of continuous exposure, theplates were evaluated using the SRB colorimetric assay as describedpreviously (V. Vichai, K. Kirtikara, Nature Prot., 2006, 1, 1112).Briefly, media was removed from the plate, and cells were fixed by theaddition of 100 μL cold 10% trichloroacetic acid in water. Afterincubating at 4° C. for 1 h, the plates were washed in water and allowedto dry. Sulforhordamine B was added as a 0.057% solution in 1% aceticacid (100 μL), and the plates were incubated at room temperature for 30min, washed in 1% acetic acid, and allowed to dry. The dye wassolubilized by adding 10 mM Tris base solution (pH 10.5, 200 μL) andincubating at room temperature for 30 min. Plates were read at λ=510 nm.IC₅₀ values were determined from three or more independent experimentsusing TableCurve (San Jose, Calif.).

IC₅₀ Value Determination for Non-Adherent Cells using MTS. In a 96-wellplate, compounds were pre-added as DMSO stocks (1% final) in triplicateto achieve final concentrations of 1 nM to 10 μM on a half log scale.DMSO and cell-free wells served as the live and dead control,respectively. Suspension cells (U-937, CEM, CA46, Daudi, HL-60, andJurkat; 10,000 cells/well) cells were distributed in 100 μL media to thecompound-containing plate. After 48 h, cell viability was assessed byadding 20 μL of a PMS/MTS solution (A. H. Cory, T. C. Owen, J. A.Barltrop, J. G. Cory, Cancer Commun., 1991, 3, 207) to each well,allowing the dye to develop at 37° C. until the live control hadprocessed MTS, and reading the absorbance at λ=490 nm. IC₅₀ values weredetermined from three or more independent experiments using TableCurve(San Jose, Calif.).

Hemolysis Assay using Human Erythrocytes. To prepare the erythrocytes,0.1 mL of human blood was centrifuged (10,000 g, 2 min). The pellet waswashed three times with saline (0.9% NaCl) via gentle resuspension andcentrifugation (10,000 g, 2 min). Following the final wash, theerythrocytes were resuspended in 0.4 mL red blood cell (RBC) buffer (10mM Na₂HPO₄, 150 mM NaCl, 1 mM MgCl₂, pH 7.4).

DMSO stocks of compounds were added to 0.5 mL tubes in singlicate (1 μL,3.3% DMSO final). The stocks were diluted with 19 μL RBC buffer.Positive control tubes contained DMSO in water, and negative controltubes contained DMSO in RBC buffer. A suspension of washed erythrocytes(10 μL) was added to each tube, and samples were incubated at 37° C. for2 hours. Samples were centrifuged (10,000 g, 2 min), and the supernatantwas transferred to a clear, sterile 384-well plate. The absorbance ofthe supernatants was measured at λ=540 nm, and percent hemolysis wascalculated relative to the average absorbance values measured for thecontrols.

Apoptosis in U-937 Cells with Annexin V-FITC and Propidium Iodide(AnnV/PI). DMSO stocks of compounds were added to a 24-well plate insinglicate (0.2% DMSO final). After compound addition, 0.5 mL of a U-937cell suspension (250,000 cells/mL) was added and allowed to incubate for21 hours. Following treatment, the cell suspensions were transferred toflow cytometry tubes and pelleted (500 g, 3 min). The media was removedby aspiration, and cells were resuspended in 200 μL AnnV binding buffer(10 mM HEPES, pH 7.4, 140 mM NaCl, 2.5 mM CaCl₂) with 5 μg/mL PI and1:90 dilution of AnnV. Samples were analyzed using flow cytometry.

Cell Cycle Arrest in Thymidine-Synchronized U-937 Cells. U-937 cellswere split to 50% confluency (250,000 cells/mL) and treated with 2 mMthymidine for 10 hours. The cells were then pelleted (500 g, 3 minutes)and washed with PBS before being resuspended in thymidine-free media andallowed to recover for 13 hours. The cells were then re-blocked with 2mM thymidine for 10 hours, and then washed with PBS as before andresuspended in media (250,000 cells/mL).

DMSO stocks of compounds were added to a 24-well plate in triplicate(0.2% DMSO final), after which 1 mL of the prepared cell suspension wasadded. Following a 16 h incubation, the cell suspensions weretransferred to 2 mL tubes and pelleted (600 g, 3 min). The media wasremoved by aspiration, and the cells were fixed with 0.5 mL of ice cold70% ethanol with vortexing. The samples were fully fixed at −20° C. for3 hours. The samples were then pelleted (1000 g, 5 min) and thesupernatant was removed via aspiration. The cells were incubated with 50μL of 5 μg/mL RNAseA in PBS for 3 hours at room temperature. Prior toreading, the samples were taken up in 150 μL of 50 μg/mL propidiumiodide in PBS and transferred to flow cytometry tubes. Samples wereanalyzed based on whole, single cells.

Tubulin Microscopy with HeLa Cells. Round, 1.5 mm coverslips (No. 1.5)were sterilized with ultraviolet light and placed in a 12-well plate.HeLa cells (100,000 cells/well) were added and allowed to adhere foreight hours. Compounds were then added as DMSO stocks to achieve a finalDMSO concentration of 1%, and the plates were returned to the incubatorfor 16 hours.

Following incubation, the media was removed, and the coverslips werefixed with 0.5 mL Microtubulin Stabilizing Buffer (MTSB, 80 mM PIPES, pH6.8, 1 mM MgCl₂, 5 mM EGTA, 0.5% TX-100)+0.5% glutaraldehyde for 10minutes at room temperature, after which the fixative was removed andthe sample was quenched with the addition of 0.5 mL of freshly-prepared1 mg/mL NaBH₄ in PBS. After a 5 min incubation, the solution was removedby aspiration and the coverslips were washed with PBS.

Coverslips were transferred to parafilm-lined culture dishes (cell-sideup), and 40 μL of 50 μg/mL RNase A in Antibody Diluting Solution (AbDil,PBS, pH 7.4, 0.2% TX-100, 2% BSA, 0.1% NaN₃) with 1:50 dilution ofanti-α-tubulin-FITC antibody was added to all samples. The samples wereallowed to incubate at room temperature in the dark for 2.5 hours, afterwhich the coverslips were washed three times with PBS+0.1% TX-100. Thesamples were then incubated for 2 minutes with 50 μL of 50 μg/mL PI inPBS. The coverslips were washed three times with PBS+0.1% TX-100, atwhich point they were mounted onto microscopy slides using Dakofluorescent mounting media, allowed to cure, and imaged on the Zeissconfocal LSM 510 (Jena, Germany).

Crystal Structure of 13-desbromo-methylester S25 was illustrated in FIG.9.

While several embodiments of the present invention have been describedand illustrated herein, those of ordinary skill in the art will readilyenvision a variety of other means and/or structures for performing thefunctions and/or obtaining the results and/or one or more of theadvantages described herein, and each of such variations and/ormodifications is deemed to be within the scope of the present invention.More generally, those skilled in the art will readily appreciate thatall parameters, dimensions, materials, and configurations describedherein are meant to be exemplary and that the actual parameters,dimensions, materials, and/or configurations will depend upon thespecific application or applications for which the teachings of thepresent invention is/are used. Those skilled in the art will recognize,or be able to ascertain using no more than routine experimentation, manyequivalents to the specific embodiments of the invention describedherein. It is, therefore, to be understood that the foregoingembodiments are presented by way of example only and that, within thescope of the appended claims and equivalents thereto, the invention maybe practiced otherwise than as specifically described and claimed. Thepresent invention is directed to each individual feature, system,article, material, kit, and/or method described herein. In addition, anycombination of two or more such features, systems, articles, materials,kits, and/or methods, if such features, systems, articles, materials,kits, and/or methods are not mutually inconsistent, is included withinthe scope of the present invention.

1. A method for treating blood cancer in a subject in need thereof,comprising administering to the subject a therapeutically effectiveamount of a compound of formula I:

or a pharmaceutically acceptable salt thereof, wherein: R¹ is —H or—CH₃; R² is —OH or —OCH₃; R³ is —H or —OH; and R⁴ is —H, or —Br when R¹is —CH₃.